After an unprotected sexual activity or a suspected contraceptive failure, levonorgestrel (Aftera) tablets are used as an emergency form of contraception. It should be used within 72 hours as it does not prevent pregnancy once implantation has occurred.
Levonorgestrel Uses:
-
Emergency contraception:
- Used to avoid pregnancy after unprotected sexual activity or potential contraceptive failure
Levonorgestrel (Aftera) Dose in Adults:
Levonorgestrel (Aftera) Dose for Emergency Contraception:
-
Females: Oral:
-
Any time during the menstrual cycle is OK for use:
-
Two-dose regimen:
- Within 72 hours of unprotected sexual activity, 1 tab of 0.75 mg should be taken as soon as feasible; the second tab of 0.75 mg should be taken 12 hours later.
-
Single-dose regimen:
- Within 72 hours of an unprotected sexual encounter, 1 tablet containing 1.5 mg should be taken as soon as feasible.
-
-
Note:
- However, if utilised within 5 days, treatment is still only moderately successful and should be made available to women up to 5 days after unprotected or insufficiently protected intercourse. In the event of an emergency, treatment should start as soon as feasible.
- When using the two-dose emergency contraceptive regimen, the second dose can be administered 12 to 24 hours after the first without losing any of its effectiveness.
Levonorgestrel (Aftera) Dose in Children:
Levonorgestrel (Aftera) Dose as an emergency contraceptive pill in adolescents:
-
Females:
- Refer to adult dosing. Not to be used prior to menarche.
Levonorgestrel Pregnancy Risk Category: X
- Women who are already pregnant should not use this product.
- No adverse effects on the mother or foetus were observed after accidental exposure during pregnancy.
- Levonorgestrel can still be used as an emergency contraceptive agent in women who have contraindications to hormonal contraceptives (eg, heart disease, migraines, liver disease)
- A rapid return to fertility can be expected after emergency contraception is used.
- Routine contraceptive measures must be taken to prevent pregnancy.
- One can immediately start using any regular contraceptive method after taking levonorgestrel; however, for a period of seven days, a barrier method (or abstinence form sexual intercourse) may be required.
Levonorgestrel use during breastfeeding:
- Breast milk contains levonorgestrel.
- The maximum concentration of levonorgestrel in breastmilk is used to determine the relative infant dosage (RID), which is then compared to a single 1.5m maternal dose.
- Breastfeeding is permitted if the RID of your medicine is less than 10%.
- Levonorgestrel's RID was calculated using a milk content of 10.7ng/mL, which resulted in an estimated daily infant dosage of 1,605ng/kg/day.
- This was achieved by giving a maternal dose of 1.5 mg of levonorgestrel 1.5mg to 12 women, who were nearly 11 weeks postpartum.
- Peak breast milk concentrations were observed between 2 and 4 hours following the dose. Then, over the next 12 hours, a rapid drop was observed.
- Levonorgestrel's breast milk half-life was 26 hours.
- Although breast milk concentrations were similar to maternal serum concentrations, they were consistently lower.
- Actual milk concentration was determined by the administration route and dosage.
- SHBG capacity also determined maternal plasma levels of levonorgestrel.
- SHBG can be enhanced by concurrent administration with estrogen and mother's postpartum status.
- Levonorgestrel can also be detected in breastmilk infants after oral administration.
- There have not been any adverse effects on the development or growth of infants. Some reports have reported isolated instances of decreased milk production.
- Levonorgestrel can be used by breastfeeding women as an emergency contraceptive.
Dose in Kidney Disease:
No dosage adjustments are provided in the manufacturer’s labeling (Use has not been studied).
Dose in Liver disease:
The manufacturer's labelling does not mention dosage modifications (Use has not been studied).
Common Side Effects of Levonorgestrel (Aftera):
-
Central nervous system:
- Fatigue
-
Endocrine & metabolic:
- Hypermenorrhea
-
Gastrointestinal:
- Nausea
- Abdominal pain
Less Common Side Effects of Levonorgestrel (Aftera):
-
Central nervous system:
- Dizziness
- Headache
-
Endocrine & metabolic:
- Suppressed menstruation
-
Genitourinary:
- Breast tenderness
Contraindications to Levonorgestrel (Aftera):
- OTC labeling
- If you are pregnant, or for regular birth control, self-medication is not recommended.
Canadian labeling:
- If long-term progestin-only contraceptives are used with levonorgestrel emergency contraception regimens, it is unknown if there are any contraindications.
- Pregnancy known or suspected
- Intolerance to levonorgestrel and any other formulation ingredient
- PV bleed(undiagnosed)
Warnings and precautions
-
Bleeding irregularities:
- After use, you may notice spotting
- If the period does not end after seven days, think about getting pregnant.
-
Ectopic pregnancy
- An ectopic pregnancy history is not a contraindication for emergency contraceptives.
- Patients with lower abdominal pain should be aware of the possibility for ectopic pregnancy.
- Especially if it occurs in women who have experienced amenorrhea and is accompanied by missed periods or PV bleeding.
Levonorgestrel (systemic): Drug Interaction
|
Antidiabetic Agents |
The therapeutic benefit of anti-diabetic agents may be reduced by hyperglycemia-associated agents. |
|
C1 inhibitors |
The thrombogenic action of C1 inhibitors may be enhanced by progestins. |
|
CYP3A4 Inducers (Moderate) |
May lower the serum level of CYP3A4 substrates (High risk with Inducers). |
|
Deferasirox |
May lower the serum level of CYP3A4 substrates (High risk with Inducers). |
|
Elexacaftor |
Hormonal contraceptives may intensify Elexacaftor's negative or hazardous effects. In particular, there may be an elevated risk for rash. |
|
Erdafitinib |
May lower the serum level of CYP3A4 substrates (High risk with Inducers). |
|
Flibanserin |
Flibanserin's serum levels may rise in response to progestins (contraceptive). |
|
Herbs (Progestogenic Properties) (eg, Bloodroot, Yucca) |
Could make progestins' harmful or hazardous effects worse. |
|
LamoTRIgine |
May lower the level of progestins in the serum (Contraceptive). |
|
Metreleptin |
May lower the level of progestins in the serum (Contraceptive). The serum concentration of progestins may rise in response to metreleptin (Contraceptive). |
|
Sarilumab |
May lower the serum level of CYP3A4 substrates (High risk with Inducers). |
|
Selegiline |
Selegiline's serum levels may rise in response to progestins (contraceptive). |
|
Siltuximab |
May lower the serum level of CYP3A4 substrates (High risk with Inducers). |
|
Thalidomide |
The thrombogenic action of thalidomide may be enhanced by progestins (contraceptive). |
|
Tocilizumab |
May lower the serum level of CYP3A4 substrates (High risk with Inducers). |
|
Triazolam |
The serum levels of triazolam may rise after using hormonal contraceptives. |
|
Voriconazole |
May raise progesterone levels in the blood (Contraceptive). The serum levels of voriconazole may rise in response to progestins (contraceptive). |
|
Risk Factor D (Consider therapy modification) |
|
|
Acitretin |
May reduce the progestins' therapeutic impact (Contraceptive). Failure with contraception is possible. Management: Progestin-only preparations shouldn't be depended upon because they may not be effective at preventing pregnancy while using acitretin. During acitretin therapy, alternative, nonhormonal methods of contraception must be used. |
|
Anticoagulants |
Anticoagulants' therapeutic effects may be lessened by progestins. More particular, some progestins and progestin-estrogen combos may have prothrombotic actions that work against any anticoagulant effects. Management: Carefully balance the progestins' possible advantages against their potential increased risk of thromboembolism and procoagulant effects. Under some conditions, use is deemed contraindicated. For particular advice, consult the relevant policies. |
|
Aprepitant |
May lower the level of progestins in the serum (Contraceptive). Treatment: Alternative or additional methods of contraception should be used for at least one month after the final dosage of aprepitant or fosaprepitant, as well as while using aprepitant or fosaprepitant. |
|
Artemether |
May lower the level of progestins in the serum (Contraceptive). Management: All women of reproductive potential who are taking artemether should think about utilising an alternative method of contraception (i.e., one that is not hormonal). |
|
Atazanavir |
May raise progesterone levels in the blood (Contraceptive). Atazanavir, however, may result in lower ethinyl estradiol levels and reduced efficiency of oral contraceptive medications. Management: When using combination estrogen/progestin medications, take into account an extra means of contraception. It is possible to utilise depot medroxyprogesterone acetate without the use of supplementary contraception. |
|
Barbiturates |
May reduce the progestins' therapeutic impact (Contraceptive). Failure with contraception is possible. Management: It is advised to use complementary, nonhormonal contraception. |
|
Bexarotene (Systemic) |
May lower the level of progestins in the serum (Contraceptive). Management: Women who are sexually active and on bexarotene should utilise two trustworthy methods of contraception (including at least one nonhormonal form). |
|
Bile Acid Sequestrants |
May lower the level of progestins in the serum (Contraceptive). Treatment: Give oral contraceptives containing progestin at least one to four hours before or six to eight hours after taking a bile acid sequestrant. |
|
Bosentan |
May lower the level of progestins in the serum (Contraceptive). Management: Do not solely rely on hormonal contraceptives for all women of reproductive potential who are taking bosentan; instead, use an alternative (i.e., non-hormonal) method of contraception. |
|
Brigatinib |
May lower the level of progestins in the serum (Contraceptive). Management: For at least 4 months following the last dosage of brigatinib, females of reproductive potential should use an alternative, non-hormonal method of contraception. |
|
CarBAMazepine |
May reduce the progestins' therapeutic impact (Contraceptive). Failure with contraception is possible. Management: It is advised to use complementary, nonhormonal contraception. |
|
Carfilzomib |
Could make progestins' thrombogenic impact stronger (Contraceptive). In patients who need carfilzomib medication, alternate, non-hormonal methods of contraception should be taken into account. |
|
Cenobamate |
Could lower the blood level of hormonal contraceptives. Management: While taking cenobamate, women should utilise additional or substitute non-hormonal birth control. |
|
Cladribine |
May reduce the hormonal contraceptives' therapeutic effect. Management: During cladribine dosage and for at least 4 weeks after the final dose in each treatment period, women who are using systemically acting hormonal contraceptives should add a barrier device. |
|
CloBAZam |
May lower the level of progestins in the serum (Contraceptive). |
|
Cobicistat |
May raise progesterone levels in the blood (Contraceptive). When treating patients who are taking cobicistat-containing medications, take into account an alternative, nonhormone-based method of contraception. Atazanavir and cobicistat are specifically contraindicated with dronabinol. |
|
CYP3A4 Inducers (Strong) |
May speed up CYP3A4 substrate metabolism (High risk with Inducers). Management: Take into account a substitute for one of the interfering medications. Specific contraindications may apply to some combinations. the relevant manufacturer's label. |
|
Dabrafenib |
May lower the serum level of CYP3A4 substrates (High risk with Inducers). Management: When possible, look for substitutes for the CYP3A4 substrate. If concurrent therapy cannot be avoided, pay special attention to the substrate's clinical consequences (particularly therapeutic effects). |
|
Dabrafenib |
May lower the level of progestins in the serum (Contraceptive). Treatment: Women who are sexually active or who are planning a pregnancy should take contraception that is highly effective, non-hormonal, and alternative for at least 2 weeks (if taking dabrafenib alone) or 4 months (if taking dabrafenib plus trametinib). |
|
Darunavir |
May lower the level of progestins in the serum (Contraceptive). Management: Take into account utilising a different or additional method of contraception. There is no requirement for supplemental contraception when using injected depot medroxyprogesterone acetate. |
|
Efavirenz |
May lower the level of progestins in the serum (Contraceptive). Management: In light of potentially decreased contraceptive effectiveness, use an extra or alternative method of contraception. Depot medroxyprogesterone administered intravenously does not seem to be involved in this interaction. |
|
Enzalutamide |
May lower the serum level of CYP3A4 substrates (High risk with Inducers). Treatment: Enzalutamide should not be used concurrently with CYP3A4 substrates that have a limited therapeutic index. Enzalutamide use, like with the use of any other CYP3A4 substrate, should be done cautiously and under close observation. |
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Eslicarbazepine |
May lower the level of progestins in the serum (Contraceptive). Management: For women who are capable of having children, alternative, non-hormonal methods of birth control should be taken into account. |
|
Exenatide |
May lower the level of progestins in the serum (Oral Contraceptive). Treatment: Oral contraceptives should be taken at least an hour before exenatide. |
|
Felbamate |
May lower the level of progestins in the serum (Contraceptive). Management: It is possible for contraceptives to fail. It is advised to use an alternative, nonhormonal method of contraception. |
|
Fosamprenavir |
The serum concentrations of the active metabolite(s) of fosamprenavir may drop when using progestins (contraceptives). Fosamprenavir may lower the level of progestins in the serum (Contraceptive). Management: Take into account utilising a different or additional method of contraception. There is no requirement for supplemental contraception when using injected depot medroxyprogesterone acetate. |
|
Fosaprepitant |
May lower the level of progestins in the serum (Contraceptive). Probably the active metabolite aprepitant is the cause of this effect. Treatment: Alternative or additional methods of contraception should be used for at least one month after the final dosage of aprepitant or fosaprepitant, as well as while using aprepitant or fosaprepitant. |
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Fosphenytoin |
May reduce the progestins' therapeutic impact (Contraceptive). Failure with contraception is possible. Management: It is possible for contraceptives to fail. It is advised to use an alternative, nonhormonal method of birth control. |
|
Ivosidenib |
May lower the level of progestins in the serum (Contraceptive). Treatment: If a patient is taking ivosidenib, consider non-hormonal contraception alternatives. |
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Lesinurad |
May lower the level of progestins in the serum (Contraceptive). Treatment: Patients on lesinurad who want reliable contraception are advised to use an additional nonhormonal method of contraception. |
|
Lixisenatide |
May lower the level of progestins in the serum (Contraceptive). Treatment: Give oral contraceptives 11 hours or more after giving lixisenatide, whichever comes first. |
|
Lopinavir |
May lower the level of progestins in the serum (Contraceptive). Lopinavir may raise the level of progestins in the serum (Contraceptive). Management: Take into account utilising a different or additional method of contraception. Without the need for supplementary contraception, injectable depot medroxyprogesterone acetate and etonogestrel implants may be utilised. |
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Lorlatinib |
May lower the serum level of CYP3A4 substrates (High risk with Inducers). Management: Avoid taking lorlatinib at the same time as any CYP3A4 substrates for which even a small drop in serum levels of the substrate could result in therapeutic failure and negative clinical outcomes. |
|
Lumacaftor |
May lower the level of progestins in the serum (Contraceptive). Management: If lumacaftor and ivacaftor are taken together, avoid using hormone-based contraceptives; instead, choose an other, non-hormonal type of contraception. |
|
MiFEPRIStone |
May reduce the progestins' therapeutic impact (Contraceptive). MiFEPRIStone may raise the level of progestins in the serum (Contraceptive). Management: During and for four weeks after mifepristone treatment, women of reproductive potential should use an efficient, nonhormonal method of contraception. |
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Mitotane |
May lower the serum level of CYP3A4 substrates (High risk with Inducers). Treatment: When administered in individuals receiving mitotane, doses of CYP3A4 substrates may need to be significantly modified. |
|
Mycophenolate |
May lower the level of progestins in the serum (Contraceptive). Management: Employing a different (nonhormonal) type of contraception should be taken into consideration. |
|
Nelfinavir |
May lower the level of progestins in the serum (Contraceptive). Management: In light of potentially decreased contraceptive effectiveness, use an extra or alternative method of contraception. Depot medroxyprogesterone administered intravenously does not seem to be involved in this interaction. |
|
Oxcarbazepine |
May lower the level of progestins in the serum (Contraceptive). Management: It is possible for contraceptives to fail. It is advised to use a second or additional nonhormonal method of contraception. |
|
Perampanel |
May lower the level of progestins in the serum (Contraceptive). Treatment: Patients should utilise an alternative method of contraception that is not hormonally based both while taking perampanel and for one month after stopping it. |
|
Phenytoin |
May reduce the progestins' therapeutic impact (Contraceptive). Failure with contraception is possible. Management: It is possible for contraceptives to fail. It is advised to use an alternative, nonhormonal method of birth control. |
|
Pitolisant |
Could lower the blood level of hormonal contraceptives. Treatment: Patients who use hormonal contraception should be urged to continue using a non-hormonal mode of contraception for at least 21 days following the cessation of pitolisant therapy. |
|
Pomalidomide |
Pomalidomide's thrombogenic action may be strengthened by progestins. Care should be taken while using hormone replacement treatment, and hormonal contraceptives are not advised, according to Canadian pomalidomide labelling. These precise guidelines are not included on the pomalidomide labelling in the US. |
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Primidone |
May reduce the progestins' therapeutic impact (Contraceptive). Failure with contraception is possible. Management: It is advised to use complementary, nonhormonal contraception. |
|
Retinoic Acid Derivatives |
May reduce the progestins' therapeutic impact (Contraceptive). Progesterone serum levels may be reduced by retinoic acid derivatives (Contraceptive). Treatment: Patients using retinoic acid derivatives should utilise two kinds of reliable contraception. Minipills that contain only microdosed progesterone and no oestrogen are regarded as ineffective forms of contraception. Adapalene, Alitretinoin (Topical), Bexarotene (Topical), and Tretinoin are exceptions (Topical). |
|
Rifamycin Derivatives |
May lower the level of progestins in the serum (Contraceptive). Failure with contraception is possible. Management: It is possible for contraceptives to fail. It is advised to use an alternative, nonhormonal method of birth control. |
|
Saquinavir |
May lower the level of progestins in the serum (Contraceptive). Management: In light of potentially decreased contraceptive effectiveness, use an extra or alternative method of contraception. |
|
St John's Wort |
May reduce the progestins' therapeutic impact (Contraceptive). Failure with contraception is possible. Management: Take into account using something other than St. John's wort. Failure with contraception is possible. It is advised to use an alternative, nonhormonal method of birth control. |
|
Sugammadex |
May lower the level of progestins in the serum (Contraceptive). Treatment: During and for 7 days after having sugammadex, patients receiving any hormonal contraceptive (oral or non-oral) should utilise an additional, non-hormonal method of contraception. |
|
Tetrahydrocannabinol and Cannabidiol |
Could lower the blood level of hormonal contraceptives. Management: Due to the potential for tetrahydrocannabinol and cannabidiol to reduce concentrations and effectiveness of hormonal contraceptives, women using hormonal contraceptives should think about including a barrier contraceptive. |
|
Tipranavir |
May raise progesterone levels in the blood (Contraceptive). Management: In light of potentially decreased contraceptive effectiveness, use an extra or alternative method of contraception. Depot medroxyprogesterone administered intravenously does not seem to be involved in this interaction. |
|
Topiramate |
May lower the level of progestins in the serum (Contraceptive). Treatment: Inform patients that this combination may result in decreased contraceptive efficacy. Think about including an additional (non-hormonal) type of birth control. |
|
Vitamin K Antagonists (eg, warfarin) |
Vitamin K antagonists' ability to prevent clotting may be lessened by progestins (contraceptives). On the other hand, several products have also been observed to have heightened anticoagulant effects. Management: To reduce the risk of thromboembolic diseases, concurrent hormonal contraceptives and coumarin derivatives should be avoided wherever possible. Think about switching to a hormonal-free method of birth control. |
|
Risk Factor X (Avoid combination) |
|
|
Encorafenib |
May lower the level of progestins in the serum (Contraceptive). |
|
Griseofulvin |
May reduce the progestins' therapeutic impact (Contraceptive). Failure with contraception is possible. |
|
Ixazomib |
May lower the level of progestins in the serum (Contraceptive). More precisely, the serum concentrations of contraceptive progestins may be lowered when ixazomib and dexamethasone are combined. Treatment: Women of reproductive potential should use a nonhormonal barrier contraceptive for the duration of their ixazomib treatment and for 90 days after. |
|
Tranexamic Acid |
Tranexamic Acid's thrombogenic impact may be enhanced by progestins (contraceptives). |
|
Ulipristal |
Ulipristal's therapeutic effects may be lessened by progestins. Ulipristal may lessen the progestins' therapeutic effects. Avoid progestins within 12 days of quitting ulipristal for uterine fibroids (Canadian indication); avoid progestins within 5 days of stopping ulipristal for emergency contraception (U.S. indication). |
Monitoring parameters:
Evaluation for pregnancy, spontaneous abortion, or ectopic pregnancy should be done if the usual (anticipated) menstrual period is delayed for longer than a week after emergency contraception, or if lower abdomen pain or persistent irregular bleeding develops.
How to administer Levonorgestrel (Aftera)?
P/O: Consider taking the dose again if vomiting occurs within two hours.
Mechanism of action of Levonorgestrel (Aftera):
- There are many ways to prevent pregnancy:
- Sperm survival and passage through the uterus is affected by thickening of cervical mucus.
- The negative feedback mechanism on hypothalamus reduces FSH and LH secretion and inhibits ovulation.
- Modifying the endometrium can affect implantation.
- Once the implantation process is complete, Levonorgestrel will no longer be effective.
- There are many ways to prevent pregnancy:
- Sperm survival and passage through the uterus is affected by thickening of cervical mucus.
- The negative feedback mechanism on hypothalamus reduces FSH and LH secretion and inhibits ovulation.
- Modifying the endometrium can affect implantation.
- Once the implantation process is complete, Levonorgestrel will no longer be effective.
Absorption:
- Rapid and complete with oral administration.
Protein binding:
- Highly albumin binding (~50%) and SHBG (~47%)
Metabolism:
- Forms inactive metabolites in the liver via CYP3A4.
Half-life elimination:
- Almost 27 hours with oral administration.
Time to peak:
- Almost 2 hours with oral administration.
Excretion:
- 45% in Urine & 32% in feces.
International Brand Names of Levonorgestrel:
- Aftera
- EContra EZ
- EContra One-Step
- Fallback Solo
- My Choice
- My Way
- New Day
- Next Choice One Dose
- Opcicon One-Step
- Plan B One-Step
- React
- Take Action
- Afterel
- Afternor
- Chrono 72
- Dopo
- ECEE
- Egianti
- Emcon
- Emergency
- Emerres
- Escapel
- Escapelle
- Estinor
- Galnique
- Glanique
- Hyan
- Indoplant
- Jadelle
- Jadelle Implant
- Lebella
- Levidon
- Levonelle
- Levonelle-2
- Madonna
- Me
- Microlut
- MIcrolut
- Microval
- Mindchange
- Norlevo
- Nulsora
- Oh God
- Ovulol
- PiDaNa
- Pill 72
- Poslov
- Postinor
- Postinor-1
- Postinor-2
- Postpill
- Pozato
- Pregnon
- Prevenelle
- Puill 72
- Ramonna
- Revoke
- Secufem
- Sino Implant II
- Upostelle
- Valenor
- Vikela
Levonorgestrel Brand Names in Pakistan:
Levonorgestrel Tablets 52 mg in Pakistan |
|
| Mirena Ius | Bayer Health Care |
Levonorgestrel Tablets 1.5 mg in Pakistan |
|
| Emkit-Ds | Zafa Pharmaceutical Laboratories (Pvt) Ltd. |
Levonorgestrel Tablets 0.75 mg in Pakistan |
|
| Ecp | Social Marketing Pakistan (Guarantee) Ltd. |
| Emergency Pills | Hansel Pharmacueutical Pvt (Ltd) |
| Emkit | Zafa Pharmaceutical Laboratories (Pvt) Ltd. |
| Medkit | Mediate Pharmaceuticals (Pvt) Ltd |
| Postinor | Medimpex Scientific Office |
 Injection.webp)