PRECAUTIONS: Before taking phenoxybenzamine, tell your doctor or pharmacist if you are allergic to it; or to other alpha blockers (e.g., phentolamine); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: blood vessel disease (e.g., cerebral arteriosclerosis, coronary artery disease), heart disease (e.g., congestive heart failure), kidney disease, lung infections.Before having surgery, tell your doctor or dentist that you are taking this medication.This drug may make you dizzy or drowsy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.Caution is advised when using this drug in the elderly because they may be more sensitive to its effects, especially dizziness.During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.It is unknown if this drug passes into breast milk. Consult your doctor before breast-feeding.
DRUG INTERACTIONS: Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: drugs to treat erectile dysfuntion-ED or pulmonary hypertension (e.g., sildenafil, tadalafil), epinephrine, other alpha blockers (e.g., prazosin), other drugs for high blood pressure (e.g., diuretics, ACE inhibitors, beta blockers).Tell your doctor or pharmacist if you also take drugs that cause drowsiness such as: certain antihistamines (e.g., diphenhydramine), anti-seizure drugs (e.g., carbamazepine), medicine for sleep or anxiety (e.g., alprazolam, diazepam, zolpidem), muscle relaxants, narcotic pain relievers (e.g., codeine), psychiatric medicines (e.g., chlorpromazine, risperidone, amitriptyline, trazodone).Check the labels on all your medicines (e.g., cough-and-cold products, diet aids, nonsteroidal anti-inflammatory drugs-NSAIDs such as ibuprofen for pain/fever reduction) because they may contain ingredients that could increase your blood pressure or contain drowsiness-causing ingredients. Ask your pharmacist about using those products safely.This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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