This website is intended to assist with patient education and should not be used as a diagnostic, treatment or prescription service, forum or platform. Always consult your own healthcare practitioner for a more personalised and detailed opinion
Hydrochlorothiazide
Please note: these are basic guidelines, refer to your doctor for a professional medical opinion.
Popular brand names:
Hexazide, Ridaq
Popular combinations:
Accuretic, Co-Tareg, Cozaar Comp, Pharmapress Co and many others
Drug group:
Thiazide diuretic
Prescription needed?
Yes
What does it do?
Hydrochlorothiazide is a safe but relatively weak diuretic drug used to treat:
Oedema (fluid retention) - in congestive heart failure, kidney disorders, cirrhosis of the liver and premenstrual syndrome
High blood pressure - usually in combination with other antihypertensives
How does it work?
Hydrochlorothiazide causes the kidneys to excrete more water from the body
In doing this it also increases the amount of potassium lost in the urine
How should it be used?
Take the drug early in the day to avoid needing to get up at night
You may need to reduce your salt intake, discuss with your doctor
It is often prescribed with potassium supplements or potassium-sparing diuretics
What is the typical dosage?
Your doctor will recommend a dosage tailored to your need, but typically:
Hypertension: 25–50mg once daily
Oedema: 25–100mg once daily, or every 2 days
How quickly will it start to work?
Within 2 hours
How long will the effects last?
6–12 hours
When should I stop using it?
Do not stop the drug without consulting your doctor
Is it safe for prolonged use?
Long term use may cause excessive loss of potassium and imbalances of other electrolytes. Regular blood tests may be done to check kidney function and potassium levels.
What are the possible side effects?
Side effects from hydrochlorothaizide are rare and mostly caused by excessive loss of potassium in the urine. Low potassium levels can increase the likelihood of irregular heart rhythms.
The following have been reported:
Less common: dizziness, muscle cramps, lethargy, headache, nausea, vomiting, constipation, temporary erectile dysfunction, gout, loss of diabetes control
Report to your doctor before taking your next dose if you experience: rash
What other considerations are important?
Dosage may be adjusted by your doctor under certain conditions.
Certain health problems: liver/kidney problems, gout, diabetes
Other medicines: Non-steroidal anti-inflammatory drugs (NSAIDs), anti-arrhythmic and digitalis drugs, corticosteroids, lithium
Pregnancy and breast-feeding: Safety in pregnancy not established, safe with breastfeeding
Children: Not usually prescribed
Over 60: Reduced dose may be necessary
Driving and hazardous work: Caution, the drug may reduce mental alertness and cause dizziness
Alcohol: Keep consumption low, increased likelihood of dehydration and hangovers