Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some of the products that may interact with this drug include: orlistat, certain drugs used to treat seizures (such as carbamazepine, phenytoin, primidone), barbiturates (such as phenobarbital, secobarbital), a certain combination HIV medication (elvitegravir/cobicistat/emtricitabine/tenofovir).

Darunavir can slow down the removal of other drugs from your body, which may affect how they work. Examples of affected drugs include certain alpha blockers (such as alfuzosin, tamsulosin), certain benzodiazepines (midazolam, triazolam), bosutinib, dronedarone, ergot alkaloids (such as dihydroergotamine, ergotamine), certain drugs to treat erectile dysfunction-ED or pulmonary hypertension (such as avanafil, sildenafil), lomitapide, pimozide, ranolazine, rivaroxaban, salmeterol, certain "statin" cholesterol drugs (such as lovastatin, simvastatin), tolvaptan, among others.

Other medications can affect the removal of darunavir from your body, which may affect how darunavir works. Examples include apalutamide, garlic supplements, certain rifamycins (rifampin, rifapentine), St. John's Wort, among others.

This medication may decrease the effectiveness of hormonal birth control such as pills, patch, or ring. This could cause pregnancy. Discuss with your doctor or pharmacist if you should use reliable backup birth control methods while using this medication. Also tell your doctor if you have any new spotting or breakthrough bleeding, because these may be signs that your birth control is not working well.

Do not take this medication with other products that contain darunavir.