Drug Interaction Report

Promazine and guanFACINE 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.

Avoid consuming grapefruit or grapefruit juice during treatment with guanFACINE, as it may increase blood levels and effects of the medication. This may cause blood pressure to fall excessively, especially when you rise from a sitting or lying position. The risk of other side effects such as drowsiness, dizziness, lightheadedness, fainting, headache, palpitations, and heart rate changes may also increase. Additionally, you should avoid or limit the use of alcohol while being treated with guanFACINE. Combining the medication with alcohol can intensify sedative and blood pressure lowering effects, which may increase the risk of falls and injury. 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. If you are using a long-acting or extended-release formulation of the medication, make sure you do not take it with a high-fat meal. Doing so results in increased absorption and elevated blood levels of the medication. Talk to your doctor or pharmacist if you have any questions or concerns.

Ask your doctor before using promazine 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.