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Drug Interactions between efavirenz and Vfend

This report displays the potential drug interactions for the following 2 drugs:

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Interactions between your drugs

Major

efavirenz voriconazole

Applies to: efavirenz and Vfend (voriconazole)

Using voriconazole together with efavirenz can alter the blood levels and effects of both medications. Specifically, voriconazole levels may decrease, which may make the medication less effective in treating your fungal infection. At the same time, efavirenz levels may increase, and you may experience more frequent and/or severe side effects. Talk to your doctor if you have any questions or concerns. Your doctor may already be aware of the interaction, but has determined that this is the best course of treatment for you and has taken appropriate precautions and is monitoring you closely for any potential complications. Contact your doctor if your conditions worsen or you have increased side effects of efavirenz such as nausea, vomiting, diarrhea, dizziness, insomnia, difficulty concentrating, abnormal dreams, depression, suicidal thoughts, and hallucinations. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

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Drug and food interactions

Moderate

efavirenz food

Applies to: efavirenz

Taking efavirenz with food increases the amount of medicine in your body, which may increase the frequency of side effects. You should take efavirenz once a day on an empty stomach, preferably at bedtime. Taking it at bedtime may make some side effects such as dizziness, trouble sleeping, drowsiness, trouble concentrating, and/or unusual dreams less bothersome. However, these symptoms may be more severe if efavirenz is used with alcohol or mood-altering (street) drugs. You should avoid driving or operating hazardous machinery until you know how the medication affects you. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

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Moderate

voriconazole food

Applies to: Vfend (voriconazole)

You may experience reduced absorption of voriconazole in the presence of food. Take voriconazole on an empty stomach 1 hour before or 2 hours after a meal unless otherwise directed by your doctor. This will make it easier for your body to absorb the medication.

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Therapeutic duplication warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.

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Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
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 interaction information available.

Further information

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

Medical Disclaimer