Interactions

• the dose of Levonelle-2 should probably be increased by 50% in women taking hepatic enzyme-inducing drugs (e.g. barbiturates, carbamazepine, phenytoin, St John's wort, the rifamycins). Therefore if a woman is taking an enzyme-inducing drug the first dose should be doubled to 1.5mg, followed 12 hours later by the usual dose of levonorgestrel of 750mcg (1,2)

Reference:

1. Drug and Therapeutics Bulletin 2000; 38 (10): 75-77.
2. NICE (October 2004).The epilepsies: the diagnosis and management of the epilepsies in adults and children in primary and secondary care.