Hytrin is in a group of drugs called alpha-adrenergic blockers. Hytrin relaxes your veins and arteries so that blood can more easily pass through them. It also relaxes the muscles in the prostate and bladder neck, making it easier to urinate.

Hytrin is used to treat hypertension (high blood pressure), or to improve urination in men with benign prostatic hyperplasia (enlarged prostate).

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

You should not use Hytrin if you are allergic to terazosin. Hytrin may cause dizziness or fainting, especially when you first start taking it or when you start taking it again. You may wish to take this medication only at bedtime if it causes you to feel light-headed. Be careful if you drive or do anything that requires you to be alert. Avoid standing for long periods of time or becoming overheated during exercise and in hot weather. Avoid getting up too fast from a sitting or lying position, or you may feel dizzy.

If you stop taking Hytrin for any reason, call your doctor before you start taking it again. You may need a dose adjustment.

Hytrin can affect your pupils during cataract surgery. Tell your eye surgeon ahead of time that you are using Hytrin. Do not stop using Hytrin before surgery unless your surgeon tells you to.

Tell your doctor about all other medications you use, especially other blood pressure medications including diuretics (water pills).

Take Hytrin exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

Your doctor may occasionally change your dose to make sure you get the best results.

Hytrin lowers blood pressure and may cause dizziness or fainting, especially when you first start taking it, or when you start taking it again. You may wish to take this medication only at bedtime if it causes you to feel light-headed. Call your doctor if you have severe dizziness or feel like you might pass out.

You may feel very dizzy when you first wake up. Be careful when standing or sitting up from a lying position.

If you stop taking Hytrin for any reason, call your doctor before you start taking it again. You may need a dose adjustment.

Your blood pressure and/or prostate will need to be checked often. Visit your doctor regularly.

If you are being treated for high blood pressure, keep using Hytrin even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure medication for the rest of your life.

Some things can cause your blood pressure to get too low. This includes vomiting, diarrhea, heavy sweating, heart disease, dialysis, a low-salt diet, or taking diuretics (water pills). Tell your doctor if you have a prolonged illness that causes diarrhea or vomiting.

Store Hytrin at room temperature away from moisture, heat, and light.

Hytrin can affect your pupils during cataract surgery. Tell your eye surgeon ahead of time that you are using this medication. Do not stop using Hytrin before surgery unless your surgeon tells you to.

If you have a history of prostate cancer, you may need a dose adjustment or special tests to safely take Hytrin.

You should not use Hytrin if you are allergic to terazosin.

FDA pregnancy category C. It is not known whether Hytrin will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication. It is not known whether terazosin passes into breast milk or if it could harm a nursing baby. Do not use Hytrin without telling your doctor if you are breast-feeding a baby.

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

If you miss your doses for several days in a row, contact your doctor before restarting the medication. You may need a lower dose.

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

Overdose symptoms may include extreme dizziness or fainting.

Hytrin may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

To prevent dizziness, avoid standing for long periods of time or becoming overheated during exercise and in hot weather.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall. Drinking alcohol can increase certain side effects of Hytrin.

Get emergency medical help if you have any of these signs of an allergic reaction to Hytrin: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you have any of these serious side effects:

• fast or pounding heartbeats or fluttering in your chest;

• feeling like you might pass out;

• swelling in your hands, ankles, or feet; or

• penis erection that is painful or lasts 4 hours or longer.

Less serious Hytrin side effects may include:

• mild dizziness;

• weakness, drowsiness;

• blurred vision;

• nausea; or

• headache.

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 other medications you use, especially:

• sildenafil (Viagra, Revatio);

• tadalafil (Cialis);

• vardenafil (Levitra);

• verapamil (Calan, Covera, Isoptin, Verelan); or

• other blood pressure medications, including diuretics (water pills).

This list is not complete and other drugs may interact with Hytrin. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.