Hypezide50 mg

Hypezide is a thiazide diuretic indicated for:

• Hypertension (established/approved use): Management of high blood pressure, either as sole therapy or in combination with other antihypertensive agents. It is widely recommended as a first-line or add-on option in current hypertension guidelines.
• Edema (established/approved use): Treatment of fluid retention (edema) associated with congestive heart failure, hepatic cirrhosis, corticosteroid and estrogen therapy, and renal dysfunction, including nephrotic syndrome, acute glomerulonephritis, and chronic renal failure.

Off-label uses (supported by clinical practice/guidelines in select cases, not a primary FDA-approved indication):

• Prevention of recurrent calcium-containing kidney stones in patients with idiopathic hypercalciuria.
• Management of nephrogenic diabetes insipidus, where Hypezide paradoxically reduces urine volume.
• Adjunct reduction of urinary calcium loss in selected patients with osteoporosis.

Each tablet contains Hydrochlorothiazide as the active ingredient, commonly available in strengths of 12.5 mg, 25 mg, and 50 mg. Hydrochlorothiazide is also formulated in fixed-dose combination products with other antihypertensive agents such as ACE inhibitors, ARBs, potassium-sparing diuretics, and beta-blockers.

Hypezide is a thiazide-type diuretic ("water pill") that helps the kidneys remove excess salt and water from the body, lowering blood pressure and reducing swelling caused by fluid retention. Hypezide has been used clinically since the late 1950s and remains one of the most widely prescribed antihypertensive medicines worldwide, and is included on the WHO Model List of Essential Medicines.

Hypezide is available as an oral tablet, usually taken once daily, either alone or combined with other blood pressure medicines.

Hypezide belongs to the thiazide diuretic class of medicines, also used as an antihypertensive agent.

Mechanism of Action

Hydrochlorothiazide acts on the distal convoluted tubule of the kidney nephron, where it inhibits the sodium-chloride (Na+/Cl-) symporter, reducing reabsorption of sodium and chloride. This increases urinary excretion of sodium, chloride, and water, producing a diuretic effect. Hydrochlorothiazide also increases excretion of potassium, magnesium, and bicarbonate, while decreasing excretion of calcium and uric acid. With long-term use, Hydrochlorothiazide also lowers blood pressure through a mild direct vasodilatory effect on blood vessel walls, reducing peripheral vascular resistance.

Pharmacokinetics

• Absorption: Well absorbed after oral administration; diuretic action begins within about 2 hours.
• Peak effect: 4 to 6 hours after dosing.
• Duration of action: Approximately 6 to 12 hours.
• Elimination: Excreted largely unchanged by the kidneys; elimination half-life is approximately 6 to 15 hours.

Hypezide is taken by mouth, with or without food. It is best taken in the morning to avoid the need to urinate frequently during the night. If a twice-daily regimen is prescribed, the second dose should ideally be taken in the early afternoon. Tablets should be swallowed with a glass of water. Blood pressure should be monitored regularly during treatment with Hypezide.

Clinically Significant Drug Interactions

• Lithium: Hypezide reduces renal clearance of lithium, increasing the risk of lithium toxicity; concurrent use should generally be avoided or lithium levels monitored closely.
• NSAIDs (e.g., ibuprofen, indomethacin): May reduce the diuretic and antihypertensive effects of Hypezide and increase the risk of renal impairment, particularly in dehydrated or elderly patients.
• Digoxin: Hypezide-induced hypokalemia or hypomagnesemia can increase the risk of digoxin toxicity and cardiac arrhythmias.
• Corticosteroids and ACTH: May intensify electrolyte depletion, particularly hypokalemia, when combined with Hypezide.
• Antidiabetic medicines (insulin, oral hypoglycemics): Hypezide can raise blood glucose levels; dose adjustment of antidiabetic therapy may be required.
• Other antihypertensive drugs and alcohol: Additive blood-pressure-lowering effect with Hypezide, which may be used therapeutically but can increase the risk of symptomatic hypotension.
• Cholestyramine and colestipol resins: Reduce absorption of Hypezide; these agents should be taken several hours apart from Hypezide.

Common Side Effects

• Increased frequency of urination (an expected effect of Hypezide)
• Dizziness or lightheadedness, especially when starting treatment or standing up quickly
• Headache
• Low blood potassium (hypokalemia)
• Upset stomach, loss of appetite
• Muscle cramps

Less Common but Serious Side Effects

• Significant electrolyte imbalances (low sodium, low magnesium, high calcium)
• Gout flare (due to raised uric acid)
• Allergic skin reactions, photosensitivity (increased sunburn risk)
• Sudden decrease in vision or eye pain (acute myopia or angle-closure glaucoma) - requires immediate medical attention and discontinuation of Hypezide
• Non-melanoma skin cancer with long-term, high cumulative dose use (see Precautions and Warnings)

Pregnancy

Hypezide crosses the placenta. It should be used during pregnancy only if clearly needed and if the potential benefit justifies the potential risk to the fetus, as thiazides have been associated with fetal or neonatal jaundice and low platelet counts in the newborn when used near term. Hypezide is not recommended for routine treatment of pregnancy-related edema or hypertension unrelated to an underlying medical condition; use only under close medical supervision and after consulting a physician.

Lactation

Hypezide is excreted into breast milk and may suppress milk production. Breastfeeding mothers should consult a physician before use, and the infant should be monitored if Hypezide is used during breastfeeding.

Electrolyte and Fluid Imbalance

Hypezide can cause hypokalemia, hyponatremia, hypochloremic alkalosis, and hypomagnesemia. Periodic monitoring of serum electrolytes is recommended, particularly with higher doses, prolonged use, in the elderly, or in patients also taking corticosteroids or digoxin.

Diabetes and Gout

Hypezide may worsen blood glucose control in patients with diabetes and can precipitate acute gout attacks by raising serum uric acid levels. Blood sugar and uric acid should be monitored in at-risk patients.

Renal and Hepatic Impairment

In significant renal impairment, Hypezide may be ineffective and can cause azotemia; use with caution and monitor renal function. In patients with hepatic cirrhosis, electrolyte changes caused by Hypezide may precipitate hepatic coma; use cautiously and monitor closely.

Photosensitivity and Skin Cancer Risk

Hypezide may cause photosensitivity reactions. Some epidemiological studies have also associated long-term use of higher cumulative doses of Hypezide with an increased risk of non-melanoma skin cancer (basal cell and squamous cell carcinoma). Patients should limit sun and UV exposure, use sun protection, and undergo regular skin examinations, especially with prolonged use of Hypezide.

Acute Myopia and Angle-Closure Glaucoma

Rarely, Hypezide can cause acute transient myopia and secondary angle-closure glaucoma, typically within hours to weeks of starting treatment. Symptoms include acute decrease in visual acuity or eye pain. Hypezide should be discontinued immediately if this occurs, and prompt medical treatment sought if intraocular pressure remains uncontrolled.

Hypersensitivity and Lupus

Hypersensitivity reactions to Hypezide may occur in patients with or without a history of allergies or bronchial asthma. Hypezide may exacerbate or activate systemic lupus erythematosus.

Overdose with Hypezide most commonly presents with signs of excessive diuresis and electrolyte depletion, such as dizziness, weakness, dry mouth, lethargy, muscle cramps, low blood pressure, and irregular heartbeat. There is no specific antidote for Hypezide overdose. If an overdose of Hypezide is suspected, seek immediate medical attention or contact a poison control center; treatment is supportive, including fluid and electrolyte replacement under medical supervision. Do not attempt to manage a Hypezide overdose at home.

Store at room temperature (below 30°C), away from light and moisture. Keep out of reach of children.

Elderly

Elderly patients are more susceptible to excessive diuresis with Hypezide, which can lead to symptomatic hypotension, dizziness, and falls. Lower starting doses and close monitoring of blood pressure and electrolytes are recommended.

Renal Impairment

See Precautions and Warnings - Hypezide may be less effective and requires cautious use in significant renal impairment.

Hepatic Impairment

See Precautions and Warnings - use Hypezide cautiously in patients with hepatic cirrhosis due to risk of precipitating hepatic coma.

Pediatric Use

See Pediatric Uses section for age- and weight-based dosing information for Hypezide.

Duration of Hypezide therapy depends on the condition being treated. For hypertension, Hypezide is generally used long-term (often lifelong) as part of ongoing blood pressure management, with periodic reassessment by a physician. For edema, treatment duration with Hypezide depends on the underlying condition and response, and the lowest effective dose should be used for the shortest necessary duration under medical guidance.

Thiazide diuretic; antihypertensive agent.

Hydrochlorothiazide inhibits the sodium-chloride symporter in the distal convoluted tubule of the nephron, reducing sodium and chloride reabsorption and increasing urinary water loss. This diuretic effect reduces circulating blood volume, and with chronic use, Hydrochlorothiazide also produces a mild direct vasodilatory effect that helps lower blood pressure.

B

Hypezide is used in children for the treatment of hypertension and edema, with dosing based on body weight and age (see Dosage and Administration). Hypezide has established pediatric dosing for infants and children under close medical supervision, particularly for edema associated with congenital heart disease or renal disorders. As with adults, electrolyte status and growth should be monitored during long-term use of Hypezide in children. Safety and efficacy of Hypezide for indications other than those studied have not been established in the pediatric population.