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Drug interactions between acetaminophen / butalbital and Plan B One-Step

Results for the following 2 drugs:
Plan B One-Step (levonorgestrel)

Interactions between your drugs


levonorgestrel ↔ butalbital

Applies to:Plan B One-Step (levonorgestrel) and acetaminophen/butalbital

Butalbital may decrease the effectiveness of levonorgestrel. If you are using low-dose contraceptives, there is an increased risk of breakthrough bleeding and unintended pregnancy during combined therapy with butalbital. Alternative or additional methods of birth control should be used while taking butalbital. If you take hormone replacement for menopause, notify your doctor if you have decreased efficacy of your hormones. You may notice symptoms of increased hot flashes, vaginal dryness or menstrual abnormalities. It is important that you tell your healthcare provider about all other medications that you are using including vitamins and herbs. Do not stop using your medications without first talking to your doctor first.

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Drug and food interactions

No results found in our database - however, this does not necessarily mean no interactions exist. Always consult with your doctor or pharmacist.

Therapeutic duplication warnings

No therapeutic duplications were found for your selected drugs.

Drug Interaction Classification

The classifications below are a guideline only. The relevance of a particular drug interaction to a specific patient is difficult to determine using this tool alone given the large number of variables that may apply.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No information available.

Do not stop taking any medications without consulting your healthcare provider.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.