LEVONORGESTREL - Watsons Health

LEVONORGESTREL

COMMON BRAND NAME(S): Plan B

GENERIC NAME(S): LEVONORGESTREL

 

Description: Levonorgestrel is a potent inhibitor of ovulation and has androgenic activity. It is a nortestosterone derivative that is an active isomer of norgestrel.

Pharmacokinetics:

Absorption: Rapid and almost complete from the GI tract (oral).

Distribution: Protein-binding: 42-68% (sex binding globulin), 30-56% (albumin). Distributed into breast milk.

Metabolism: Hepatic; converted to sulfate and glucuronide conjugates.

Excretion: Via urine and via faeces (lesser extent).

Levonorgestrel prevents pregnancy after birth control failure (such as a broken condom) or unprotected sex by preventing the release of an egg (ovulation) during your menstrual cycle. It also makes vaginal fluid thicker to help prevent sperm from reaching an egg (fertilization) and changes the lining of the uterus (womb) to prevent attachment of a fertilized egg.

This medication will not stop an existing pregnancy or protect you or your partner against sexually transmitted diseases (such as HIV, gonorrhea, chlamydia).

This medication may not work well in women over a certain weight (for example, greater than 164 pounds or 74 kilograms).

How to use levonorgestrel

If you are taking the over-the-counter product to self-treat, read all directions on the product package before taking this medication. If you have any questions, consult your pharmacist. If your doctor has prescribed this medication, take it as directed.

Take this medication by mouth as soon as possible after unprotected sex. Your instructions for use depend on the brand you take. Therefore, check the label on your brand and ask your doctor or pharmacist if you have any questions. Take as directed, usually 2 tablets at once; or take 1 tablet and then take the second tablet 12 hours after the first tablet. This medication may be taken with or without food. This medication works best when it is taken within 72 hours (3 days) after unprotected sex.

If you vomit within 2 hours of taking a dose of this medication, contact your doctor to ask if you need to repeat the dose.

After you take this medication, the time when your period comes and how much you bleed may change. Tell your doctor right away if your period is more than 7 days late. You may need to take a pregnancy test.

If you think you may have a serious medical problem, get medical help right away.

Tell your doctor or pharmacist promptly if any of these effects persist or worsen:

  • nausea/vomiting
  • abdominal pain
  • tiredness
  • dizziness
  • changes in vaginal bleeding
  • breast tenderness
  • diarrhea
  • headache

Tell your doctor right away if you have severe lower stomach pain (especially 3 to 5 weeks after taking levonorgestrel).

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

  • rash
  • itching/swelling (especially of the face/tongue/throat)
  • severe dizziness
  • trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

  • Allergic reaction to medication
  • Medical history of unexplained vaginal bleeding
  • This drug may make you dizzy
  • Tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products) before having surgery
  • This medication must not be used during pregnancy
  • Consult your doctor before breast-feeding

Consult your doctor regarding the precautions mentioned above.

 

Interactions:

Other medications can affect the removal of levonorgestrel from your body, which may affect how levonorgestrel works, such as:

  • Griseofulvin
  • Modafinil
  • rifamycins (such as rifampin, rifabutin)
  • John’s wort
  • drugs used to treat seizures (such as barbiturates, carbamazepine, felbamate, phenytoin, primidone, topiramate)

HIV drugs (such as nelfinavir, nevirapine, ritonavir)

Overdose with this medication is very unlikely. However, if overdose is suspected, contact a poison control center or emergency room immediately.

Notes

Keep all regular medical and laboratory appointments.

Missed Dose

If you miss a dose, contact your doctor right away.

Storage

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

 

Brands:

Also marketed as:

Mirena [ Bayer ]

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