Hydrochlorothiazide Tablets

Hydrochlorothiazide is one of the most established thiazide diuretics available by prescription, and we carry it as an oral tablet in two strengths so customers can match a pack to their usual regimen.

What Is Hydrochlorothiazide?

Hydrochlorothiazide tablets contain the active ingredient hydrochlorothiazide, a thiazide-type diuretic taken by mouth. It works by reducing sodium and chloride reabsorption in the distal renal tubule, which increases urine output and lowers circulating fluid volume. This action lowers blood pressure and reduces the swelling associated with fluid retention, or edema. Hydrochlorothiazide is used on its own or alongside other blood pressure medicines, such as Lisinopril, when a single agent does not bring readings to target. Customers comparing options for managing blood pressure can also browse our Blood Pressure category for related treatments we carry.

Essential Facts and Dosing

Adult dosing typically starts at 12.5 mg to 25 mg once daily, taken in the morning with or without food; some regimens use up to 50 mg daily, though higher doses raise the risk of electrolyte disturbance without adding much extra blood-pressure benefit. Tablets are usually swallowed whole with a glass of water. The diuretic effect begins within a couple of hours, peaks around four to six hours later, and the blood-pressure-lowering effect builds over one to two weeks of regular use.

Common effects include increased urination, dizziness on standing, and mild shifts in sodium or potassium. Hydrochlorothiazide can interact with lithium, raising lithium levels, and with NSAIDs, which may blunt its diuretic and blood-pressure effects; combining it with an ACE inhibitor, ARB, or other antihypertensive is common practice and usually intentional. Periodic blood tests to check kidney function, electrolytes, and glucose are a normal part of monitoring, especially early in treatment or after a dose change.

Available Strengths and Package Sizes

We currently list Hydrochlorothiazide tablets in the following strengths and quantities, so customers can choose a pack that fits their prescribed regimen and planned supply.

Available quantities vary by strength. The 12.5 mg tablet is offered in packs of 30, 60, 90, 120, 180, or 360 pills, while the 25 mg tablet is offered in packs of 90, 120, 180, 270, or 360 pills. All listed options are oral Hydrochlorothiazide tablets.

Important Safety Notes

• Contraindications: Hydrochlorothiazide should not be used by people with anuria or known hypersensitivity to hydrochlorothiazide or another sulfonamide-derived medicine. A general history of sulfonamide allergy should be discussed with a prescriber before treatment.
• Fluid and electrolyte balance: Excessive thirst, severe weakness, muscle cramps, confusion, fainting, or a marked reduction in urination can indicate dehydration, low blood pressure, kidney problems, or an electrolyte disturbance and should be assessed promptly.
• Gout: Hydrochlorothiazide can raise uric acid levels and may trigger gout in susceptible people, so a history of gout should be reviewed with the prescriber.
• Vision changes: Rarely, hydrochlorothiazide can cause acute eye pain or a sudden reduction in vision. These symptoms require urgent medical assessment.
• Prescription and ordering status: Hydrochlorothiazide is classified as a prescription medicine in Canada, and Health Canada's Drug Product Database lists approved hydrochlorothiazide products; public drug-plan coverage varies by province, plan, and formulary. We do not require a prescription document to accept an order, but the medicine is best used under a prescriber's guidance for dosing and monitoring.
• Storage: Store the tablets at room temperature, between 20°C and 25°C, protected from light and moisture.

Our pharmacist-backed support team is available every day by chat, phone, or email to help confirm which strength and pack size suit an existing regimen.