Phenoxybenzamine is used to control blood pressure and reduce sweating in people with pheochromocytoma (tumor of the adrenal gland).

Phenoxybenzamine may also be used for purposes not listed in this medication guide.

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

Call your doctor if you have fast heartbeats. You may need to be treated with an additional medication.

Store phenoxybenzamine at room temperature away from moisture and heat.

Usual Adult Dose for Pheochromocytoma:

Initial dose: 10 mg orally twice daily
Maintenance dose: 20 to 40 mg orally 2 to 3 times daily until an optimal dosage (as judged by blood pressure control) is obtained.

You should not use phenoxybenzamine if you are allergic to it.

Tell your doctor if you have ever had:

• coronary artery disease (hardened arteries);

• a lung infection; or

• kidney disease.

Tell your doctor if you are pregnant.

You should not breastfeed while using phenoxybenzamine.

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include fast heart rate, vomiting, dizziness, or fainting.

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Avoid driving or hazardous activity until you know how phenoxybenzamine will affect you. Your reactions could be impaired.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy.

Drinking alcohol with this medicine can cause side effects.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using phenoxybenzamine and call your doctor at once if you have severe dizziness or if you feel like you might pass out.

Common side effects of phenoxybenzamine may include:

• stuffy nose;

• mild dizziness or drowsiness;

• blurred vision;

• trouble having an orgasm;

• upset stomach; or

• tired feeling.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Tell your doctor about all your other medicines, especially:

• reserpine;

• tizanidine;

• epinephrine (Epi-Pen), norepinephrine; or

• blood pressure medications.

This list is not complete. Other drugs may affect phenoxybenzamine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Keep all appointments with your doctor and the laboratory. Your blood pressure should be checked regularly to determine your response to phenoxybenzamine.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.