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Hydrochlorothiazide

Most Commonly Used
Hydrochlorothiazide 25mg Tab
Qualitest Pharmaceuticals Inc
Pill Identification: 3571 V 
Drug Image file DrugItem_2609.JPG
Hydrochlorothiazide 12.5mg Tab
Actavis Inc. Elizabeth LLC
Pill Identification: LOGO  |  20
Drug Image file DrugItem_16657.JPG
Hydrochlorothiazide 50mg Tab
Qualitest Pharmaceuticals Inc
Pill Identification: 3572 V 
Drug Image file DrugItem_6040.JPG
Hydrochlorothiazide 12.5mg Cap
Mylan Pharmaceuticals Inc
Pill Identification: MYLAN 810 MYLAN 810 
Drug Image file DrugItem_5349.JPG
Hydrochlorothiazide 12.5mg Tab
Drug Image file default-drug-image.png
Also See:
  • Answers to Frequently-Asked Questions (FAQs)
  • Other Class Related Drugs
  • Additional Patient Usage Statistics


Overview Information on Hydrochlorothiazide
Pharmacist Tip
If you forget a dose of hydrochlorothiazide, take it as soon as you remember, unless it is time for your next dose. In that case, skip the missed dose and return to your regular schedule.     
Hydrochlorothiazide is a kind of medicine called a thiazide diuretic or more commonly, a water pill. Your doctor might prescribe hydrochlorothiazide if you have high blood pressure and are retaining water. Hydrochlorothiazide helps reduce blood pressure by helping your kidneys to produce more urine and expel extra water and salt.

Your body might retain this water due to various conditions. While hydrochlorothiazide can help your doctor control your blood pressure, hydrochlorothiazide will not cure your condition. You should keep taking hydrochlorothiazide for as long as your doctor tells you to, even if you start feeling better.

Before you start taking hydrochlorothiazide, it's important to tell your doctor if you have any allergies or medical conditions. Tell your doctor if you have taken an antibiotic medicine called a "sulfa" and had any problems or an allergic reaction to it.

Be sure to give your doctor a complete list of all the medicines you are taking, including over-the-counter medicines and herbal supplements.

You should also let your doctor know if you are pregnant, plan to become pregnant, or are breast-feeding before taking hydrochlorothiazide. If you get pregnant while taking hydrochlorothiazide, tell your doctor right away.

Hydrochlorothiazide may cause side effects such as drowsiness. Alcohol may make this side effect worse. Your doctor may want you to avoid drinking alcohol while taking hydrochlorothiazide. Hydrochlorothiazide may also make your skin more sensitive to the sun. Be sure to protect yourself from exposure to the sun when you go outside.

Follow your doctor's instructions carefully when taking hydrochlorothiazide, particularly those related to changes in your diet and exercise routine. After you take hydrochlorothiazide, you will pass more urine and more frequently. Remember to take hydrochlorothiazide at those times of the day when you have access to a bathroom.

Hydrochlorothiazide can cause some side effects. If you have any side effect that becomes severe or does not go away, tell your doctor. Some common side effects of hydrochlorothiazide include:

  • Cramps and muscle weakness
  • Dizziness, headache, or thirst
  • Stomach pain, nausea, vomiting, diarrhea, or loss of appetite
  • Dizziness
  • Blurred vision
Let your doctor know right away, or call 911 in an emergency, if these symptoms are severe or won't go away:

  • Abnormal bleeding or bruising
  • A skin rash, hives, or peeling of the skin
  • Swelling of the face, lips, or tongue
  • Difficulty breathing or swallowing


Clinical Review by Jodi Grimm, RPh and Ann Ciemnoczolowski, MS, ELS on May 15, 2013
Hydrochlorothiazide is a kind of medicine called a thiazide diuretic or more commonly, a water pill. Your doctor might prescribe hydrochlorothiazide if you have high blood pressure and are retaining water. Hydrochlorothiazide helps reduce blood pressure by helping your kidneys to produce more urine and expel extra water and salt.

Your body might retain this water due to various conditions. While hydrochlorothiazide can help your doctor control your blood pressure, hydrochlorothiazide will not cure your condition. You should keep taking hydrochlorothiazide for as long as your doctor tells you to, even if you start feeling better.

Before you start taking hydrochlorothiazide, it's important to tell your doctor if you have any allergies or medical conditions. Tell your doctor if you have taken an antibiotic medicine called a "sulfa" and had any problems or an allergic reaction to it.

Be sure to give your doctor a complete list of all the medicines you are taking, including over-the-counter medicines and herbal supplements.

You should also let your doctor know if you are pregnant, plan to become pregnant, or are breast-feeding before taking hydrochlorothiazide. If you get pregnant while taking hydrochlorothiazide, tell your doctor right away.

Hydrochlorothiazide may cause side effects such as drowsiness. Alcohol may make this side effect worse. Your doctor may want you to avoid drinking alcohol while taking hydrochlorothiazide. Hydrochlorothiazide may also make your skin more sensitive to the sun. Be sure to protect yourself from exposure to the sun when you go outside.

Follow your doctor's instructions carefully when taking hydrochlorothiazide, particularly those related to changes in your diet and exercise routine. After you take hydrochlorothiazide, you will pass more urine and more frequently. Remember to take hydrochlorothiazide at those times of the day when you have access to a bathroom.

Hydrochlorothiazide can cause some side effects. If you have any side effect that becomes severe or does not go away, tell your doctor. Some common side effects of hydrochlorothiazide include:

  • Cramps and muscle weakness
  • Dizziness, headache, or thirst
  • Stomach pain, nausea, vomiting, diarrhea, or loss of appetite
  • Dizziness
  • Blurred vision
Let your doctor know right away, or call 911 in an emergency, if these symptoms are severe or won't go away:

  • Abnormal bleeding or bruising
  • A skin rash, hives, or peeling of the skin
  • Swelling of the face, lips, or tongue
  • Difficulty breathing or swallowing


Clinical Review by Jodi Grimm, RPh and Ann Ciemnoczolowski, MS, ELS on May 15, 2013