Are You Taking Plan B Correctly? 6 Mistakes Women Make With The Morning-After Pill
You Take Certain Pills

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There are some medications that can reduce the effectiveness of the morning-after pill, according to Health Unit. These include:
- Anti-HIV drugs
- Antibiotics
- Rifabutin (brand name Mycobutin)
- Griseofulvin (brand name Gris-PEG)
- John’s wort
- Anticonvulsants (epileptic seizure medications such as Lyrica, Neurontin and Tegretol)
- Rifampicin (brand names Rifadin and Rimactane)