Drug Interaction Report

Hydroxychloroquine can increase the blood levels and effects of silodosin. This may cause blood pressure to fall excessively and heart rate to increase, especially when you rise from a sitting or lying position. The risk of other side effects such as dizziness, lightheadedness, fainting, headache, flushing, nasal congestion, heart palpitations, and priapism (prolonged and painful erection unrelated to sexual activity) may also increase. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. Let your doctor know if you develop these symptoms while using silodosin and they do not go away on their own or they become troublesome. Avoid driving or operating hazardous machinery until you know how the medication affects you, and use caution when getting up from a sitting or lying position. 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.

You may want to limit your consumption of grapefruit or grapefruit juice during treatment with hydroxychloroquine. Grapefruit juice can significantly increase the blood levels and effects of hydroxychloroquine, which may result in an irregular heart rate or other conduction disturbances. Hydroxychloroquine should also be taken with food or milk to reduce the incidence of stomach upset. Talk to your doctor if you have any questions or concerns. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with hydroxychloroquine. 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.

Taking silodosin with food can reduce the risk and/or severity of side effects. Therefore, silodosin should be administered with or immediately after a meal.