Drug Interaction Report

Promethazine and terazosin may have additive effects in lowering your blood pressure. You may experience headache, dizziness, lightheadedness, fainting, and/or changes in pulse or heart rate. These side effects are most likely to be seen at the beginning of treatment, following a dose increase, or when treatment is restarted after an interruption. Let your doctor know if you develop these symptoms and they do not go away after a few days or they become troublesome. Avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medications affect 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.

Ask your doctor before using terazosin together with ethanol (alcohol). Using terazosin with ethanol (alcohol) can lower your blood pressure. This can cause dizziness or feeling like you might pass out, especially when getting up from a sitting or lying position. This may be more likely to occur when you first start taking either of these medications. You may need a dose adjustment or need your blood pressure checked more often if you take both medications. You may develop flushing, warmth or redness under your skin or tingly feeling after alcohol intake (especially in you are of Asian descent) and should be advised to avoid alcohol or limit your intake. 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.

Ask your doctor before using promethazine together with ethanol (alcohol). This can cause uncontrollable movements, agitation, seizures, severe dizziness or fainting, coma, very deep sleep, irregular heartbeats, and high or low body temperature. Use caution when driving, operating machinery, or performing other hazardous activities, these medicaions may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities. 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.