Drug Interactions between Allegra and tasimelteon

Consuming large amounts of certain fruit juices, including grapefruit, orange and apple, may decrease the levels of fexofenadine in your body. Fexofenadine should be taken with water and refrain from drinking large amounts of grapefruit, orange, or apple juice. This will make it easier for your body to absorb the medication.

Food can delay the absorption of tasimelteon, which may increase the amount of time it takes for the medication to work. You should take tasimelteon without food at the same time each night before going to bed. If you are a smoker, there is a possibility that tasimelteon may not work as well for you due to reduced blood levels of the medication in smokers compared to nonsmokers. You should avoid or limit the use of alcohol while being treated with tasimelteon. It can increase some of the side effects including dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. Talk to your doctor or pharmacist if you have any questions or concerns.