Diseases Symptoms Drugs Injuries Surgeries Vitamins Pediatric Symptoms
  home         about us         support center         contact us         terms of service         site map


Brand & Generic Names


Basic Information

  • Habit forming? No
  • Prescription needed? Yes
  • Available as generic? No
  • Drug class: Antihypertensive, diuretic (thiazide)


  • Controls, but doesn't cure, high blood pressure.
  • Reduces fluid retention (edema) caused by conditions such as heart disorders and liver disease.
  • Treatment for Raynaud's disease.

Dosage & Usage Information

How to take:
Tablet or capsule--Swallow with 8 oz. of liquid. If you can't swallow whole, crumble tablet or open capsule and take with liquid or food. Don't exceed dose.

When to take:
At the same times each day.

If you forget a dose:
Take as soon as you remember up to 2 hours late. If more than 2 hours, wait for next scheduled dose (don't double this dose).

What drug does:
Expands and relaxes blood vessel walls to lower blood pressure.
Forces sodium and water excretion, reducing body fluid.
Relaxes muscle cells of small arteries.
Reduced body fluid and relaxed arteries lower blood pressure.

Time lapse before drug works:
4 to 6 hours. May require several weeks to lower blood pressure.

Don't take with:
Non-prescription drugs without consulting doctor.
See Interaction Section and consult doctor.


Extreme weakness; loss of consciousness; cold, sweaty skin; weak, rapid pulse; cramps; weakness; drowsiness; coma.


  • Dial 911 (emergency) or O (operator) for an ambulance or medical help. Then give first aid immediately.
  • If patient is unconscious and not breathing, give mouth-to- mouth breathing. If there is no heartbeat, use cardiac massage and mouth-to-mouth breathing (CPR). Don't try to make patient vomit. If you can't get help quickly, take patient to nearest emergency facility.
  • See EMERGENCY Information.

Possible Adverse Reactions or Side Effects


    Irregular heartbeat, Discontinue. Seek weak pulse, fast emergency treatment. heartbeat, difficult breathing, chest pain.


    Nightmares, vivid dreams, drowsiness, dizziness, dry mouth, stuffy nose.


  • Blurred vision, abdominal pain, nausea, vomiting, difficult breathing.
  • Mood change, headache, dry mouth, muscle pain, urgent urination, weakness, tiredness, weight gain or loss, runny nose, joint or muscle pain, agitation, depression, rash, appetite loss, weakness and faintness when arising from bed or chair, constipation.


  • Sore throat, fever, mouth sores; jaundice.
  • Diminished sex drive, numbness or tingling in hands or feet.

Warnings & Precautions

Don't take if:

  • You are allergic to any thiazide diuretic drug or prazosin.
  • You are depressed.
  • You will have surgery within 2 months, including dental surgery, requiring general or spinal anesthesia.

Before you start, consult your doctor:

  • If you are allergic to any sulfa drug.
  • If you have gout, impaired circulation in brain or have had a stroke, coronary heart disease (with or without angina), kidney disease or impaired liver function.
  • If you experience lightheadedness or fainting with other antihypertensive drugs.
  • If you are easily depressed.

Over age 60:

  • Adverse reactions and side effects may be more frequent and severe than in younger persons, especially dizziness and excessive potassium loss.
  • Don't stand while taking. Sudden changes in position may cause falls. Sit or lie down promptly if you feel dizzy. If you have impaired brain circulation or coronary heart disease, excessive lowering of blood pressure should be avoided. Report problems to your doctor immediately.

Risk to unborn child outweighs drug benefits. Don't use.

Drug passes into milk. Avoid drug or discontinue nursing until you finish medicine. Consult doctor for advice on maintaining milk supply.

Infants & children:
Not recommended.

Prolonged use:

  • You may need medicine to treat high blood pressure for the rest of your life.
  • Talk to your doctor about the need for follow-up medical examinations or laboratory studies.

Skin & sunlight:
May cause rash or intensify sunburn in areas exposed to sun or sunlamp.

Driving, piloting or hazardous work:
Don't drive or pilot aircraft until you learn how medicine affects you. Don't work around dangerous machinery. Don't climb ladders or work in high places. Danger increases if you drink alcohol or take medicine affecting alertness and reflexes, such as antihistamines, tranquilizers, sedatives, pain medicine, narcotics and mind-altering drugs.

Don't discontinue without consulting doctor.


  • First dose likely to cause fainting. Take it at night and get out of bed slowly next morning.
  • Hot weather and fever may cause dehydration and drop in blood pressure. Dose may require temporary adjustment. Weigh daily and report any unexpected weight decreases to your doctor.
  • May cause rise in uric acid, leading to gout.
  • May cause blood sugar rise in diabetics.

Possible Interaction with Other Drugs

------------------------ -----------------------
Acebutolol Increased antihypertensive effect.
Dosages may require adjustments.
ACE inhibitors*: Decreased blood pressure.
Allopurinol Decreased allopurinol effect.
Amphetamines* Decreased prazosin effect.
Amphotericin B Increased potassium.
Antidepressants, Dangerous drop in blood pressure.
tricyclic (TCA)* Avoid combination unless under
medical supervision.
Antidiabetics*, other Increased blood sugar.
Antihypertensives* Increased antihypertensive effect.
Dosages may require adjustments.
Barbiturates* Increased polythiazide effect.
Carteolol Increased antihypertensive effect.
Cholestyramine Decreased polythiazide effect.
Chlorpromazine Acute agitation.
Cortisone drugs* Excessive potassium loss that
causes dangerous heart rhythms.
Digitalis Excessive potassium loss that
preparations* causes dangerous heart rhythms.
Diuretics*, other Increased effect of other thiazide
Estrogens* Decreased prazosin effect.
Indapamide Increased diuretic effect.
Indomethacin Decreased polythiazide effect.
Lithium Increased effect of lithium.
MAO inhibitors* Blood pressure drop. Increased
polythiazide effect.
Nicardipine Blood pressure drop. Dosages may
require adjustment.
Nifedipine Weakness and faintness when arising
from bed or chair.
Nimodipine Dangerous blood pressure drop.
Nitrates* Possible excessive blood pressure
Non-steroidal Decreased prazosin effect.
Opiates* Weakness and faintness when arising
from bed or chair.
Potassium Decreased potassium effect.
Probenecid Decreased probenecid effect.
Sotalol Decreased antihypertensive effect.
Sympathomimetics* Decreased prazosin effect.
Terazosin Decreases effectiveness of
Verapamil Weakness and faintness when arising
from bed or chair.

Possible Interaction with Other Substances

--------------- ---------------
Alcohol: Dangerous blood pressure drop.
Beverages: None expected.
Cocaine: Increased risk of heart block and
high blood pressure.
Licorice. Excessive potassium loss that
causes dangerous heart rhythms.
Marijuana: Possible fainting, increased blood
pressure. Avoid.
Tobacco: Possible spasm of coronary
arteries. Avoid.

Dserun mollit anim id est laborum. Lorem ipsum and sunt in culpa qui officias deserunt mollit. Excepteur plus sint occaecat the best cupidatat nonr proident, sunt in culpa qui officia deserunt mollit anim id est laborum. September 24, 2004
read more


Excepteur plus sint occaecat the best cupidatat nonr proident, sunt in culpa qui officia deserunt mollit.
Support forums
Help desk
home       about us      affiliates     contact us       terms of service      

© 2005 All right reserved