i-Pill, Levonorgestrel

Contemporary reproductive healthcare relies heavily on emergency contraception (EC). The i-Pill, which contains the synthetic progestogen levonorgestrel, is a leading example. This single-dose formulation has revolutionized the global conversation about post-coital birth control, largely due to its high accessibility and proven effectiveness in preventing unintended pregnancies across diverse populations.

Levonorgestrel works by delaying or stopping ovulation, but its success is highly time-sensitive: it must be taken as soon as possible after unprotected intercourse, and no later than 72 hours. This importance is underscored by its global use (over 100 countries) and its status as an essential medicine by the World Health Organization (WHO). Patients should receive counseling about its potential side effect of temporarily altering the menstrual cycle (e.g., earlier, later, or heavier bleeding).

Levonorgestrel is a synthetic progestin of the second generation. It primarily works by inhibiting ovulation and thickening the cervical mucus. Its pharmacological strength and positive safety profile set it apart from earlier agents.

Formulations frequently incorporate excipients like lactose monohydrate, maize starch, magnesium stearate, and colloidal silicon dioxide. Although these substances are clinically inactive, they play a significant role in affecting tablet stability, absorption kinetics, and shelf life.

The i-Pill typically contains 1.5 mg of levonorgestrel in a single oral tablet. In some markets, 0.75 mg tablets are available, which should be taken twice within 12 hours. Prolonged use of combined oral contraceptives containing levonorgestrel and ethinyl estradiol expands its range of applications.

This combination establishes the basis for many combined oral contraceptives. Ethinyl estradiol improves cycle regulation, while levonorgestrel guarantees contraceptive reliability. Together, they strike a balance between efficacy and tolerability.

Norethindrone, a first-generation progestin, provides contraceptive advantages but has a slightly reduced progestational profile compared to levonorgestrel. Levonorgestrel exhibits greater receptor affinity, which results in improved potency at lower doses.

Progesterone is a natural hormone produced by the body, crucial for maintaining pregnancy. Levonorgestrel, a synthetic version, replicates its effects but is available in oral form, more stable, and better suited for contraceptive products.

Norgestrel is a racemic mixture. Levonorgestrel is the active enantiomer, offering enhanced pharmacodynamic efficiency. Consequently, levonorgestrel provides similar effectiveness with lower dosing requirements.

Both are oral progestins, but levonorgestrel is viewed as more potent. Norethindrone carries extra androgenic effects, sometimes resulting in acne or weight changes, which are not as noticeable with levonorgestrel.

This combination supports numerous monophasic and triphasic contraceptives. Ethinylestradiol promotes cycle regularity, while levonorgestrel sustains contraceptive effectiveness. The pairing has been thoroughly researched, showing consistent efficacy rates surpassing 99% with ideal use.

Pharmacological nuance emphasizes levonorgestrel as the active isomer of norgestrel. This distinction enables lower doses to reach therapeutic equivalence.

Etonogestrel is commonly utilized in subdermal implants, offering long-lasting contraception. Levonorgestrel is adaptable, found in pills, intrauterine devices, and as emergency contraception. Both substances are highly effective, yet they vary in their delivery methods and length of action.

Drospirenone, a more recent progestin, shows anti-mineralocorticoid effects, helping to lessen bloating and fluid retention. In comparison, levonorgestrel focuses on its effectiveness and broad clinical application, with minimal issues related to electrolyte imbalances.

In Spanish-speaking nations, this combination of levonorgestrel vs ethinilestradiol to be a widely accepted as a contraceptive method. Clinical results are consistent with global observations: dependable pregnancy prevention paired with a strong record of safety.

Norgestimate is less androgenic and is frequently favored for patients who are susceptible to acne or seborrhea. Levonorgestrel, on the other hand, continues to be a cornerstone because of its strong efficacy and well-established pharmacokinetic profile.

Desogestrel is frequently used in progestin-only pills and has a lower androgenic index. Levonorgestrel is more powerful but somewhat more androgenic, affecting prescriber decisions according to patient requirements.

While levonorgestrel focuses on effective ovulation suppression, drospirenone offers extra advantages such as enhanced fluid balance and mood stabilization for certain patients. The clinical situation determines the selection.

Both agents effectively inhibit ovulation. Etonogestrel’s implant offers a consistent long-term release, while levonorgestrel delivers quick post-coital intervention or prolonged action in intrauterine devices.

Plan B is basically a branded version of levonorgestrel emergency contraception. The two are chemically the same; the differences mainly come down to branding and distribution.

Norethindrone acetate is often used to address abnormal uterine bleeding and endometriosis. Levonorgestrel, on the other hand, leads the contraceptive market, especially in emergency and long-acting intrauterine products.

Aviane is a commonly prescribed low-dose combined oral contraceptive that includes 20 mcg of ethinyl estradiol and 100 mcg of levonorgestrel. The reduced estrogen level helps to limit adverse effects while ensuring effective contraception.

The i-Pill works due to its active ingredient, levonorgestrel, a potent synthetic progestin. Its main strategy is to prevent or delay ovulation by suppressing the surge of luteinizing hormone (LH). This action removes the egg as a potential target for sperm, virtually eliminating the chance of fertilization.
If ovulation is already underway, levonorgestrel provides two secondary safeguards:

• It alters cervical mucus, making it thicker and impeding sperm from traveling up the reproductive tract.
• It reduces the uterus's lining receptivity, making it harder for a fertilized egg (if one formed) to implant.

This rapid, biochemical, and time-sensitive approach is what makes it a comprehensive and effective emergency contraceptive when used promptly.

Levonorgestrel creates a complex, multi-stage barrier to prevent pregnancy. Its effectiveness depends on when it's taken:

• Before Ovulation: It stops the follicle from rupturing, preventing the egg from being released.
• Around Ovulation: It slows sperm movement by thickening cervical mucus and changes how the egg and sperm travel within the fallopian tubes.

• After Fertilization: It alters the lining of the uterus (endometrium), making implantation of a fertilized egg highly unlikely.

By disrupting multiple stages of the reproductive process, levonorgestrel effectively prevents conception. Crucially, the pill does not work once implantation has already happened, which distinguishes emergency contraception from methods that induce abortion.

The key difference between regular birth control pills and the i-Pill is their purpose. Standard oral contraceptives are taken daily to provide continuous, long-term pregnancy prevention by maintaining steady hormone levels. They also offer benefits like cycle regulation and reduced menstrual pain.
In contrast, the i-Pill is a single-use emergency solution taken after unprotected sex or contraceptive failure. It contains a much higher dose of only levonorgestrel (unlike regular pills that often combine estrogen and progestin) and does not provide the cycle-regulating benefits. Therefore, the i-Pill must be understood as a contingency measure, not a substitute for routine, daily birth control.

The effectiveness of levonorgestrel can be compromised by certain medications. Specifically, drugs and herbal supplements (like St. John's Wort) that speed up the liver's metabolism (by inducing cytochrome P450 enzymes) can lower the concentration of levonorgestrel in the blood, thereby reducing its efficacy as an emergency contraceptive.
Examples of these "enzyme inducers" include drugs used for epilepsy (e.g., phenytoin, carbamazepine), tuberculosis (rifampicin), and some HIV treatments. When a patient is taking these substances, healthcare providers may need to recommend alternative or additional contraceptive methods. Apart from these specific drug interactions, levonorgestrel is generally safe and minimally interferes with most other medications. Knowing these specific interactions is vital for ensuring reliable protection.

The i-Pill offers quick, single-dose contraception following unprotected sex, but it is intended only for emergency use, not as a regular daily birth control method. Its effectiveness is highly time-dependent: it must be taken as soon as possible to interrupt the process of ovulation.

• It works best when taken within 24 hours.
• It is usable up to 72 hours, though its efficacy significantly decreases after that point.
• It is not an abortifacient as it cannot end an established pregnancy.

In summary, the i-Pill is a time-bound, contingency measure, serving as a backup when routine contraception fails or is missed.

After taking emergency contraception, the timing of the next period may change. Many women experience a slight delay, but the period could also arrive earlier. The nature of the flow may also be different, potentially being lighter, heavier, or involving spotting.
These changes are temporary, reflecting the pill's immediate impact on your hormones, not a long-term cycle problem. You should generally expect your period within seven days of its usual date. If your period is delayed by more than one week, it is important to take a pregnancy test. Note that some intermittent spotting is common 2 to 7 days after taking the pill.

Combined oral contraceptives (COCs), which contain both levonorgestrel (a progestin) and ethinyl estradiol (an estrogen), are frequently prescribed to regulate erratic menstrual cycles. The estrogen component stabilizes the uterine lining (endometrium), while the progestin prevents ovulation, resulting in predictable, scheduled withdrawal bleeding.

These pills offer several benefits, including achieving cycle regularity, reducing menstrual pain (dysmenorrhea), and easing heavy bleeding (menorrhagia). Crucially, COCs are not the same as emergency contraception because their purpose and dosing are entirely different. When selecting a method, practitioners must consider the patient's preferences, metabolic health, and any reasons to avoid estrogen. For severe heavy bleeding, a device like the levonorgestrel intrauterine system (IUS) is another option.

The primary goal of levonorgestrel is to immediately reduce the risk of pregnancy following contraceptive failure or unprotected sex. It achieves this by delaying or blocking ovulation and thickening cervical mucus to impede sperm, thereby decreasing the likelihood of fertilization during the fertile window.
Its efficacy is highly time-dependent: it works best when taken within 24 hours and is only effective up to 72 hours. Patients should be aware that other options exist with longer windows of efficacy, such as the copper IUD (up to five days) or ulipristal acetate (up to 120 hours). Furthermore, individuals with a higher body weight may experience reduced effectiveness and should be counseled on alternative emergency methods.

Emergency contraception (EC) is necessary whenever a person has had unprotected sex or when their primary birth control method has failed. The goal is to intervene quickly and privately to reduce the chance of conception.
Situations warranting EC include:

• Barrier failure (like a condom breaking or slipping).
• Hormonal lapses (such as forgetting routine pills or delaying an injection).
• Unplanned exposure (using no method, or relying on withdrawal/coitus interruptus).
• It is a required component of post-sexual assault care.
• It is needed if a patient is taking enzyme-inducing drugs that reduce the effectiveness of their regular hormonal birth control.

Best practice dictates prompt access, clear guidance, and follow-up pregnancy testing if the next period is delayed.

Levonorgestrel is highly effective in treating menorrhagia (abnormally heavy menstrual bleeding) when delivered through an intrauterine system (IUS). The IUS provides a localized dose that acts directly on the uterine lining (endometrium), significantly reducing the blood vessels and thickness of the tissue. This results in a substantial and often rapid decrease in menstrual blood loss.
This therapeutic approach greatly improves the patient's quality of life, preventing issues like chronic fatigue and anemia. It is a major alternative to more invasive surgical options for heavy bleeding, such as a hysterectomy or endometrial ablation, and can decrease the need for such procedures.

Levonorgestrel is an effective treatment for endometriosis, a condition causing severe pain and infertility due to the growth of uterine lining tissue outside the uterus. Levonorgestrel works by using its anti-inflammatory and antiproliferative qualities to lessen the cyclical growth of these misplaced tissue implants.
By reducing the estrogen-driven function of the uterine lining, levonorgestrel-based therapies significantly relieve pelvic pain and painful periods (dysmenorrhea). When administered through an intrauterine device (IUD), it offers localized suppression, causing the tissue implants to shrink (atrophy). While not a cure, this approach helps manage symptoms, reduces reliance on general painkillers, and provides a valuable alternative or addition to surgery for many patients.

Polycystic Ovary Syndrome (PCOS) is a complex hormonal condition defined by the lack of ovulation, excess male hormones (hyperandrogenism), and metabolic issues. To manage this, levonorgestrel, usually combined with ethinyl estradiol (estrogen), is used to regulate the menstrual cycle.
This combined treatment helps to:

• Restore a predictable pattern of withdrawal bleeding.
• Reduce the risk of endometrial hyperplasia (thickening of the uterine lining) caused by chronic lack of ovulation.
• Bring about a hormonal balance that may also improve some androgen-related symptoms.

However, its use requires careful evaluation, especially for patients who have a high risk of cardiovascular or metabolic problems, where other hormonal therapies might be safer.

Levonorgestrel is used not just as emergency contraception, but also as a key component in long-term birth control strategies. Its versatile pharmacological properties are utilized in several highly effective forms of sustained contraception:

• Intrauterine Systems (IUS): Provide pregnancy prevention for up to five years.
• Combined Oral Pills: Taken daily to both prevent conception and regulate menstrual cycles.
• Subdermal Implants: Deliver a steady, sustained systemic release of the hormone.

These diverse, extended-use methods transform levonorgestrel from a one-time emergency solution into a cornerstone for sustained, everyday contraceptive care, demonstrating its broad applicability in meeting various reproductive needs.

For emergency contraception, levonorgestrel is typically taken as a single oral dose of 1.5 mg for a swift hormonal effect. While a split-dose regimen of two 0.75 mg tablets taken 12 hours apart is available in some areas, both methods provide comparable effectiveness. The simpler single-dose method is generally preferred because it makes it easier for patients to stick to the regimen (improving adherence). Notably, the drug is well-absorbed orally and its absorption is not affected by food.

The most widely recommended way to take levonorgestrel for emergency contraception is a single 1.5 mg oral dose, which should be administered as soon as possible after unprotected intercourse to maximize effectiveness. While an alternative regimen exists (two 0.75 mg doses spaced 12 hours apart), the single-dose is preferred. It is important to note that the pill should not be repeated within the same menstrual cycle unless the user has another episode of high-risk sexual exposure.

The success of levonorgestrel as an emergency contraceptive is highly dependent on how quickly it is taken. The sooner it is administered, the better it prevents ovulation and conception.

• Its efficacy is maximal (around 95%) within the first 24 hours.
• Effectiveness is still strong but begins to decrease between 24 and 48 hours (around 85%).
• Effectiveness significantly drops between 48 and 72 hours (around 58%).

Because its power is markedly reduced after 72 hours, alternative methods, such as inserting a copper intrauterine device (IUD), should be considered.

If the levonorgestrel dose is vomited within two hours of taking it, the user must immediately take another tablet. For those using the two-dose 0.75 mg regimen, delaying the second tablet past 16 hours may lessen its effectiveness; therefore, this dose should be completed right away. Remember not to exceed the recommended frequency within one menstrual cycle. If your next period is delayed by more than seven days, it is essential to get a pregnancy test.

While taking levonorgestrel more than once in the same cycle poses no major toxicity risk, it is not recommended as a routine practice. Repeated dosing can cause menstrual irregularities, such as unexpected bleeding or delayed periods, and generally disrupt the normal endocrine function, making cycles unpredictable. For anyone who finds themselves needing emergency contraception multiple times, the best course of action is to switch to a reliable, long-term method of contraception for greater stability and dependability.

There is no reason to prescribe levonorgestrel to women who have reached menopause because their reproductive function has naturally ended. Furthermore, there is very little pharmacological data available concerning the effects of this drug in postmenopausal individuals.

Levonorgestrel should not be used if pregnancy is known (it is contraindicated) because it offers no benefit once implantation has occurred. While the drug has not been linked to birth defects (teratogenic effects) if exposure happens during pregnancy, it is still not recommended for routine use in pregnant individuals. For women who are breastfeeding, occasional use is considered safe, despite the fact that a small amount of the hormone has been found to pass into breast milk.

Breastfeeding mothers can safely use levonorgestrel for emergency contraception with minimal risk to their infant. Only a small amount of the hormone transfers into the breast milk. As an optional precaution to further reduce the infant's exposure, mothers can choose to interrupt nursing for 3 to 4 hours immediately after taking the pill. The use of levonorgestrel has not been shown to negatively affect milk production.
Safety and Contraindications

• Safety: Safe for occasional emergency use during breastfeeding.
• Contraindications: None explicitly stated in this text, but the general context implies it's safe unless the mother wishes to reduce the minimal transfer by delaying feeding.

Levonorgestrel is approved for use as emergency contraception in adolescents who have already started menstruating (post-menarcheal individuals). In this age group, its safety and effectiveness are comparable to those observed in adult women. However, it is crucial to provide thorough education and counseling to ensure adolescents understand how to use the pill correctly and to encourage them to adopt a standard, long-term contraceptive method rather than relying on emergency contraception regularly.

Since the liver is the primary way the body metabolizes levonorgestrel, it is contraindicated (should be avoided) in women with severe liver disease.
For individuals with kidney issues:

• Mild to moderate renal impairment does not require a change in dosage, as it doesn't significantly affect the drug's clearance.
• More advanced kidney problems still require caution and medical supervision.

Mild liver dysfunction is not an absolute bar to treatment, and occasional emergency use may be permitted under a doctor's guidance. Ultimately, doctors must use clinical judgment to balance the drug's benefits against the risks of altered metabolism in any patient with compromised organ function.

The most common reaction to levonorgestrel is transient gastrointestinal discomfort. Nausea is a frequent symptom that typically starts within a few hours and resolves naturally. Vomiting is rare, but a clinical concern because it can prevent the drug from being absorbed properly.
Symptoms usually start 2 to 8 hours after the dose. To manage them, it's advised to have light meals or ginger tea, and an anti-nausea medication (antiemetic) can be used if necessary. A key point is that if you vomit within two hours of taking the pill, you should typically take another dose.
It's also helpful to stay hydrated and get rest. If symptoms are severe or persist, you should seek medical attention to ensure they aren't caused by a different issue.

After taking the emergency dose, it's common to experience breakthrough bleeding or spotting between periods. The effect on your next menstrual cycle is highly variable: your period could be earlier or delayed, and the flow might be lighter or heavier than usual. This spotting often occurs 2 to 7 days after taking the pill. These shifts are due to temporary changes in the uterine lining (endometrium) and are not a sign of permanent cycle disruption. If your period is delayed by more than 7 days, a pregnancy test is recommended. Normal cycle timing usually resumes with the period following the next one.

A small number of people report feelings of tiredness, lightheadedness, or a faint/vasovagal sensation. These effects are usually minor and go away on their own. If you feel severely dizzy, you should not drive or operate machinery. Make sure you stay well-hydrated and eat properly. Seek medical help immediately if you faint (syncope), experience ongoing vertigo, or notice any neurological changes.

Headaches (cephalalgia) and breast tenderness (mastalgia) are possible side effects caused by temporary changes in hormone levels. This discomfort usually goes away on its own within 24 to 72 hours. You can use simple pain relievers (analgesics) to help with the pain, and supportive bras or cool compresses may ease breast soreness. However, you should seek immediate medical attention for an intense, sudden headache (thunderclap headache) or severe pain in only one breast.

Acute weight gain is rare after taking a single emergency dose. Any observed fluctuation is typically minor and reversible, often due to temporary fluid retention or minor changes in appetite, rather than a lasting increase in body fat. If you experience bloating, try to moderate your salt intake and maintain regular physical activity. Note that while rare with the emergency pill, long-acting levonorgestrel methods have been linked to appetite changes in a few users.

Levonorgestrel and norethindrone are both progestins with comparable overall side effect profiles, but they differ in their androgenic (male hormone-like) activity. Levonorgestrel has a stronger androgenic effect than norethindrone, which means levonorgestrel may be more likely to cause acne or oily skin (seborrhea) in sensitive individuals.

• Levonorgestrel is generally better at preventing ovulation but carries a higher potential for acne, breast pain, and irregular bleeding.
• Norethindrone is frequently associated with breakthrough bleeding and headaches, and while it can have androgenic effects, they are typically milder.
• In practice, the specific dosage and pill formulation often impact real-world side effects more than the chemical structure alone.

The long-term effects are most relevant for continuous-release devices like intrauterine systems (IUS). Common experiences include irregular bleeding during the first few months, followed later by the possible cessation of periods (amenorrhea). Other effects that some users may experience are functional ovarian cysts, acne, and mood changes.
Most minor side effects will lessen after the initial adjustment period. However, serious issues are rare; you must seek immediate medical attention for pelvic pain with a fever, severe bleeding, or signs that the device might have moved or been expelled.

In addition to nausea, patients may also experience other mild digestive issues, such as indigestion (dyspepsia), abdominal cramps, or diarrhea. These symptoms are generally minor.
To relieve this discomfort, try having small, frequent meals and using antacids. If you have ongoing abdominal pain and there is still a possibility of pregnancy, you must be checked for an ectopic pregnancy (pregnancy outside the uterus).

The most obvious short-term effect of taking the emergency dose is a change to your menstrual cycle. This commonly involves the next period starting a few days earlier or later, and the flow (intensity and duration) may also be different from your usual period. However, your menstrual cycle usually returns to its normal timing by the month after that.

A true allergic reaction (hypersensitivity) is uncommon, but when it happens, it may appear as hives (urticaria), itching (pruritus), or swelling beneath the skin (angioedema).

If you experience swelling of the face, wheezing, or difficulty breathing, stop the medication immediately and seek emergency medical care. Minor rashes usually clear up well with oral antihistamines and moisturizing creams (topical emollients).

Some people report temporary changes in emotion, such as mood swings, irritability, or short-term feelings of unhappiness (dysphoria), after taking the dose. These feelings are likely related to the rapid shifts in neurosteroids (hormones affecting the brain) caused by the medication.
These symptoms are usually temporary and will resolve on their own. However, if the symptoms are intense or continue for a long time, they should be evaluated to rule out an existing mood disorder or other possible causes.

Because levonorgestrel has a wide therapeutic range, accidentally taking more than the recommended dose is unlikely to cause severe poisoning or toxicity.
Overdosing may, however, lead to more intense versions of the common side effects, specifically:

• Pronounced nausea, vomiting, and stomach pain.
• Temporary irregular vaginal bleeding or spotting.
• Increased headaches, dizziness, and fatigue.

There is no specific cure (antidote) for an overdose; treatment focuses on managing symptoms and providing support.
Initial steps include assessing the time and amount of the drug taken. Activated charcoal may be considered if a significant amount was ingested within the past hour and if appropriate for the patient. Treatment also involves controlling nausea with anti-emetic drugs and ensuring hydration and electrolyte balance. If the patient had unprotected sex, they should be evaluated for pregnancy and advised to get follow-up testing if their period is missed.

While frequent, higher-than-recommended use of the drug rarely leads to severe long-term consequences, the primary concern is endocrine disruption. This disruption can cause prolonged, unpredictable menstrual cycles and unexpected bleeding.
It's important to understand that repeatedly using emergency contraception does not substitute for a regular method of birth control. Individuals using it frequently should consider switching to a reliable ongoing method, such as a copper IUD, levonorgestrel IUS, or combined oral contraceptives. If your menstrual cycles remain erratic for over two to three months, you should seek medical advice.

Certain antiepileptic drugs (such as phenytoin and carbamazepine) are enzyme-inducers that speed up the liver's breakdown of levonorgestrel. This process significantly lowers the amount of levonorgestrel in the bloodstream, potentially reducing its effectiveness as an emergency contraceptive, especially when taken near the time of ovulation. For patients on these strong enzyme-inducers, clinical best practice recommends non-oral emergency contraception alternatives.

• Other medications that pose a risk include phenobarbital, primidone, topiramate, and oxcarbazepine.
• Alternatives to consider are the copper intrauterine device (IUD) or ulipristal acetate.
• It is crucial to document the patient's concomitant medications and advise them to use backup contraception.

Most common routine antibiotics do not significantly interfere with levonorgestrel effectiveness. The main exceptions are drugs that interact with the liver enzyme CYP3A:

• Rifamycin-class antibiotics (like rifampin and rifabutin) are strong inducers, meaning they dramatically reduce levonorgestrel levels and lessen its contraceptive effect.
• The antifungal griseofulvin is a weak inducer that might also reduce effectiveness.
• In contrast, azole antifungals (like ketoconazole and fluconazole) generally increase levonorgestrel levels, which does not affect efficacy but warrants monitoring for side effects.

If a patient is taking a rifamycin or griseofulvin, it is best to choose a non-oral emergency contraception method if available.

The herbal supplement St. John’s Wort (Hypericum perforatum) is a powerful inducer of certain liver enzymes and transport proteins (CYP3A and P-glycoprotein). This action speeds up the removal of levonorgestrel from the body, resulting in lower drug availability and therefore a potential risk of contraceptive failure. The fact that it is a natural product does not mean it is safe or without strong pharmacological effects.

• These induction effects can persist for several days after the patient stops taking the herb.
• It is advised to recommend backup birth control methods or an alternative form of emergency contraception.

Medication reconciliation (a careful check of all prescriptions, over-the-counter products, and herbal supplements) is essential to prevent complications. If there is any question about a potential drug interaction, the safest course is to switch to an emergency contraception method that is not affected by liver enzymes.

• Specifically, review any use of enzyme-inducing medications within the last four weeks.
• When strong inducers are present, prefer the copper IUD or ulipristal acetate.
• Always educate the patient on the correct timing of the pill, how to manage vomiting, and when to perform a pregnancy test if their period is late.

The effectiveness of levonorgestrel as an emergency contraceptive decreases the longer the time elapsed since unprotected intercourse. The highest protection is achieved within the first 24 hours. After 72 hours, the ability to prevent pregnancy drops significantly, and other options offer better protection in this extended timeframe. Beyond 72 hours, the copper IUD (effective for up to 5 days) or ulipristal acetate (effective for up to 120 hours) are the preferred alternatives.

Emergency contraception is meant for contingency situations only, not as a regular form of birth control. Frequent use can result in unpredictable menstrual cycles and a risk of lapses in pregnancy prevention. Once the emergency situation has passed, it is crucial to establish a reliable, ongoing contraceptive method.

• Recommended ongoing methods include combined oral contraceptives, progestin-only pills, implants, or IUDs.
• Also, advise on using condoms for simultaneous protection against STIs.

Several pre-existing medical conditions (comorbidities) necessitate caution when using levonorgestrel. Severe liver disease is a contraindication because it affects how the drug is metabolized. Conditions that impair gut function, such as malabsorption syndromes or recent bariatric surgery, can reduce oral absorption. Additionally, higher body weight may decrease the medication's effectiveness, making alternative options preferable.

• Avoid using levonorgestrel in cases of severe liver impairment.
• For those with higher BMIs, advise the use of the copper IUD or ulipristal when possible.

• While cardiovascular or metabolic risk alone is not a formal contraindication, a careful, individual risk assessment is recommended.

If vomiting occurs within two hours of taking the pill, the medication may not have been absorbed. In this case, a repeat dose is usually advised, or an alternative emergency method should be used if the vomiting persists. Any ongoing abdominal pain or a missed period requires a pregnancy test and an assessment to rule out an ectopic pregnancy. Seek immediate care for severe pain, fainting (syncope), or heavy bleeding.

Although allergic reactions (hypersensitivity) are rare, their occurrence prohibits any future use of the drug. Symptoms of a reaction may include hives (urticaria), swelling (angioedema), or difficulty breathing (bronchospasm). If any allergic symptoms appear, stop using the medication immediately. Standard anaphylaxis protocols should be initiated if the reaction is severe.

Levonorgestrel is ineffective once a pregnancy has implanted and does not cause abortion. Therefore, a known or suspected pregnancy is a contraindication for taking the emergency dose.

• Pregnancy testing should be performed if your period is more than 7 days late.
• If you experience pain or abnormal bleeding, seek an urgent medical assessment for a potential ectopic pregnancy (pregnancy outside the uterus).

Because the liver extensively metabolizes the drug, severe liver dysfunction is a contraindication for use. In these cases, non-hormonal alternatives should be chosen instead.

• For urgent contraceptive needs, the copper IUD should be considered.
• If contraceptive planning is complex due to liver issues, the patient should be referred for a liver specialist (hepatology) consultation.

Before starting any hormonal treatment, the cause of undiagnosed abnormal bleeding must be fully investigated. The primary goal of this diagnostic process is to eliminate complications like pregnancy issues, structural problems (e.g., fibroids), or blood clotting disorders (coagulopathy). Therefore, levonorgestrel use should be postponed until a proper gynecologic evaluation determines the underlying cause.

While the single, acute dose of levonorgestrel for emergency contraception is generally well tolerated, patients with pre-existing cardiovascular problems should be treated with caution. Since the systemic impact of this single dose is limited, the primary concern lies in the overall clinical context.

• It is important to evaluate baseline risks such as how well hypertension is controlled, any history of ischemic symptoms, or arrhythmias.
• For ongoing contraception, non-estrogen alternatives should be chosen to avoid potential blood pressure changes.
• Patients should be alert to and seek care for chest pain, new neurological symptoms, or a severe headache following the dose.
• When there is uncertainty, a discussion of risks versus benefits is crucial to align the treatment with the patient's heart health.

Patients with metabolic conditions require individualized advice. A single emergency dose of levonorgestrel generally does not affect blood sugar control. However, body size can influence how the drug works and its overall effectiveness.

• Since increased body weight can reduce efficacy, the copper IUD or ulipristal acetate should be considered as alternatives when possible.
• Glycemic monitoring is crucial for individuals whose blood sugar has been recently unstable or who have taken steroids.
• For long-term contraception, prioritize highly effective, weight-neutral methods like IUDs or implants.
• Choosing a precise and reliable future method is key to reducing the need for emergency pills and improving contraceptive security.

Progestin-only emergency contraception (like levonorgestrel) is associated with a much lower risk of blood clots (thrombosis) than combined hormonal methods because it does not contain estrogen (ethinyl estradiol). Despite this low risk, a history of venous thromboembolism (VTE) or a clotting disorder (thrombophilia) still requires careful review.
Levonorgestrel is generally suitable for emergency use even with a history of VTE because the exposure is brief. Following the emergency use, patients should consider non-estrogen, long-acting birth control alternatives. Immediate medical evaluation is crucial for any new symptoms like leg swelling, chest pain when breathing (pleuritic pain), or shortness of breath (dyspnea).

Conditions that can be influenced by progestins—such as migraines with aura, certain mood disorders, and hormone-sensitive cancers—require personalized guidance. Although the drug exposure from a single emergency dose is brief, caution is still advised.

• For active hormone-sensitive cancer, consult the treating specialist before using any hormonal strategy.
• For patients with a migraine with aura, monitor closely for any neurological changes, and consider a non-hormonal method for ongoing contraception.
• If significant mood swings occur, schedule a follow-up assessment if the emotional symptoms persist for more than a few days.

Your menstrual period timing often changes after taking this medication. If your period is delayed by more than one week from when you expected it, you need further evaluation.

• Specifically, take a pregnancy test if your period is more than seven days late.
• Seek immediate medical attention for severe abdominal pain or fainting to check for an ectopic pregnancy (a pregnancy outside the uterus).

Emergency contraception should only be used as a backup and not as a regular method of birth control. Using it repeatedly in a short period can cause irregular menstrual cycles and may decrease the reliability of protection.

• Frequent use may result in spotting, unscheduled bleeding, or delayed periods.
• While severe toxicity from repeat dosing is not expected, the predictability of your cycle declines.
• To stabilize your cycle and reduce risk, you should transition to a reliable, long-acting method of contraception.

Counseling after the emergency event is vital to ensure the patient establishes continuous contraception, thereby preventing future urgent situations.

• Discussions should cover the effectiveness of different methods: IUDs and implants offer the highest effectiveness, while methods like pills, patches, and rings require strict, consistent use.
• Also, cover dual protection by discussing condom use to reduce the risk of STIs.
• Finally, establish a clear follow-up plan to quickly start or resume a reliable, regular contraceptive method.

Obstacles such as logistics, cost, and social stigma limit a person's reproductive autonomy (the freedom to make their own choices). Implementing practical solutions is therefore essential.

• Solutions include providing information on local healthcare services, telehealth options, and financial assistance programs.
• Advance provision of emergency contraception (giving it out before it's needed) should be supported where legal.
• Offering culturally competent counseling is also key to improving acceptance and consistent use of contraception.

Keep the tablets at a controlled room temperature, ensuring they are protected from too much heat, moisture, and direct sunlight. Since bathrooms are often humid, they are not recommended for storage. The ideal temperature range is 20−25∘C (68−77∘F), though brief times between 15−30∘C (59−86∘F) are usually acceptable. To minimize exposure to the environment, keep the tablets in their original blister packaging until you are ready to use them.

The drug's stability is only guaranteed up to the expiration date listed on the label if it has been stored correctly. Exposure to heat and humidity will cause the medication to degrade faster.
Always check the expiration date before giving or taking the medication yourself. Do not use the tablets if the blister packaging is damaged, or if the tablets themselves look discolored or crumbly.

Never consume tablets that are expired or damaged. Proper disposal methods are important for protecting both people in the household and the environment.

• If possible, use local community drug take-back or disposal programs.
• If a take-back program is unavailable, mix the tablets with an unappealing substance (such as used coffee grounds) and seal them in a bag before placing them in the regular household trash.
• Always remove or block out any personal information on the packaging before discarding it.

Even though the medication is packaged in single-dose blister packs, careful management (stewardship) is critical in homes with children or individuals at risk of accidental ingestion.

• Store the medication out of sight and reach, ideally in a locked cabinet.
• Keep the tablets in their sealed blister packs until the moment of use to prevent accidental swallowing.
• Inform other household members about what the medication is for and how it is meant to be used.