Levonorgestrel

From Anvita Health Wiki

Contents 1 Introduction 2 Indications 3 Dosage 4 Adverse-effects 5 Drug-interactions 6 Mechanism-of-action 7 More General Terms 8 Additional Terms 9 Internet Database 10 References

Introduction

• Tradename: Norplant.

Indications

• contraceptive: 6 implants subdermal every 5 years
• emergency (post coital) contraceptive
• excessive menstrual bleeding in women who use intrauterine contraception

Dosage

• Capsule: (subdermal implantation: 36 mg)
• Each Norplant silastic capsule releases 80 ug/day for 6-18 months, after which 25-30 ug/day is released & maintained for a total effective duration of < 5 years.
• Mirena: intrauterine device

Adverse-effects

• common (> 10%)

• prolonged menstrual flow, spotting

• less common (1-10%)

• amenorrhea, irregular menstrual cycles, scanty bleeding, pain or itching at implant site, headache, nervousness, breast discharge, myalgia, leukorrhea, vaginitis, nausea, dizziness, dermatitis, acne, change in appetite, weight gain

• uncommon (< 1%)

• infection at site of implantation
  
• drug adverse effects of hormonal contraception

Drug-interactions

• carbamazepine
• phenytoin
• rifampin
  
• drug interaction(s) of beta-adrenergic receptor antagonists with oral contraceptives

Mechanism-of-action

• prevents ovulation or fertilization by altering the fallopian tubal transport of sperm or ova
• not effective once implantation has occurred or the woman is already pregnant

More General Terms

• norgestrel (Ovrette)

Additional Terms

• levonorgestrol-releasing intrauterine system (LNG-IUS)

Internet Database

PubChem: 13109

References

1. The Pharmacological Basis of Therapeutics, 9th ed. Gilman et al, eds. Permagon Press/McGraw Hill, 1996
2. Kaiser Permanente Northern California Regional Drug Alert
3. Kaiser Permanente Northern California Regional Drug Formulary, 1998
4. FDA Approves Additional Use for IUD Mirena to Treat Heavy Menstrual Bleeding in IUD Users

levonorgestrel (Norplant, Mirena)