Rifampicin and contraception
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Editor, -The article 'Common questions about the management of meningococcal disease' (Aust Prescr 1999;22:117-8) discusses the efficacy of oral contraception following chemoprophylaxis for contacts of meningococcal disease. I have discussed this issue with the Family Planning Association and believe in-depth advice on how to manage contraception while taking rifampicin should be given to the contact.
Appropriate advice is: 'In the case of short term concurrent drug treatment, a barrier method should be used both during treatment and for seven days after discontinuation. If this would continue into the next oral contraceptive tablet-free interval, the woman should skip the tablet-free interval an start the next pack as soon as she has finished the pack in use.'1
This is an important issue, as advising women to stop oral contraception or use another method for four weeks after completion of chemoprophylaxis, increases the risk of non-compliance and causes further stress to the contact.
It is also excessive and not necessary.
South East Sydney Public Health Unit
Debra Rowett and Tricia Warrick, Drug and Therapeutics Information Service(DATIS), Pharmacy Department, Repatriation General Hospital, Daw Park, South Australia, comment:
The letter from Giulietta Pontivivo highlights the importance of providing clear advice to ensure both compliance with rifampicin and ongoing effective oral contraceptive use. It was not the intent of the article to recommend that oral contraceptives be ceased whilst on concomitant rifampicin and for four weeks after cessation of rifampicin, but rather to emphasise that, if using hormonal contraception, additional non-hormonal contraception is required over this time. This recommendation is in accordance with the Australian Medicines Handbook2 and other standard reference texts.3,4,5 Importantly, the British National Formulary2 specifically highlights that 'rifampicin is such a potent enzyme-inducing drug that even if a course lasts for less than 7 days the additional contraceptive precautions should be continued for at least 4 weeks after stopping it.' Given the serious consequences of unwanted pregnancy, the recommendation of using additional non-hormonal contraception for four weeks was included in accordance with other standard reference sources. As conflicting opinion and advice is potentially confusing for both health professionals and patients, inclusion of this matter in the forthcoming revised NHMRC guidelines for the control of meningococcal disease in Australia would be welcomed.
- Geurts TBP, Goorissen EM, Sitsen JMA. Summary of drug interactions with oral contraceptives. Carnforth: Parthenon Publishing Group;1993. p. 72-3
- Misan G, Rossi S, Gabb G, Vitry A, Abbott F, Hill R, et al, editors. Australian Medicines Handbook. 1st ed. Adelaide: Australian Medicines Handbook Pty Ltd.; 1998. p. 5-76.
- Mehta DK, editor. British National Formulary. Number36 (September 1998). London: British Medical Association and Royal Pharmaceutical Society of Great Britain; 1998. p. 351-2.
- Parfitt K, editor. Martindale - The Extra Pharmacopoeia.32nd ed. London: Royal Pharmaceutical Society; 1999. p. 1433.
- Stockley IH, editor. Drug Interactions. 5th ed. London: Pharmaceutical Press; 1999. p. 430.