Hydrocl is a prescription diuretic medication containing hydrochlorothiazide, specifically formulated for the clinical management of edema associated with congestive heart failure, hepatic cirrhosis, and renal dysfunction, as well as for the treatment of hypertension. As a thiazide diuretic, it operates by inhibiting sodium reabsorption in the distal convoluted tubule of the nephron, promoting excretion of sodium and water, thereby reducing extracellular fluid volume and lowering blood pressure. Its well-established efficacy profile and predictable pharmacokinetics make it a cornerstone therapy in cardiovascular and renal medicine, particularly for patients requiring controlled fluid elimination without drastic electrolyte shifts. This agent is typically employed in chronic management protocols where sustained volume control is necessary.

Features

• Contains 12.5 mg, 25 mg, or 50 mg of hydrochlorothiazide per tablet
• White, round, scored tablets with “HYDROCL” debossed on one side
• Available in bottles of 30, 90, and 500 tablets
• Chemical name: 6-chloro-3,4-dihydro-2H-1,2,4-benzothiadiazine-7-sulfonamide 1,1-dioxide
• Molecular formula: C₇H₈ClN₃O₄S₂
• Half-life: approximately 5.6–14.8 hours
• Peak plasma concentration: 1.5–4 hours post-administration
• Protein binding: approximately 40%
• Excretion primarily renal (≥61%) and fecal (≤20%)

Benefits

• Effectively reduces edema and fluid retention in patients with cardiac, hepatic, or renal conditions
• Lowers blood pressure through volume reduction and direct vasodilatory effects
• Demonstrates a predictable dose-response relationship for tailored therapeutic management
• Compatible with long-term therapy when monitored appropriately
• Reduces cardiac preload and afterload, decreasing myocardial oxygen demand
• May potentiate the effects of other antihypertensive agents when used in combination therapy

Common use

Hydrocl is primarily indicated for the management of edema resulting from congestive heart failure, cirrhosis of the liver, corticosteroid and estrogen therapy, and renal dysfunction, including nephrotic syndrome. It is also approved for the treatment of hypertension, either as monotherapy or in combination with other antihypertensive drugs. In clinical practice, it is frequently used off-label for calcium nephrolithiasis prophylaxis in hypercalciuric patients and for diabetes insipidus treatment due to its paradoxical antidiuretic effect. The medication is typically incorporated into chronic treatment regimens rather than acute care scenarios.

Dosage and direction

Dosage must be individualized based on patient response and electrolyte balance. For edema: initial dose is 25–100 mg once daily or divided doses. Maintenance may be 25–100 mg daily or intermittently. For hypertension: initial dose is 25 mg once daily. Maintenance may be 25–100 mg daily. Maximum dose: 100 mg daily. Administration should occur in the morning to prevent nocturia. Tablets should be swallowed whole with a full glass of water. Consistent timing relative to meals is recommended to maintain stable pharmacokinetics. Renal impairment requires dosage adjustment: avoid use if CrCl <30 mL/min.

Precautions

Periodic assessment of blood electrolytes (particularly potassium, sodium, chloride, and bicarbonate) is essential. Monitor for signs of fluid or electrolyte imbalance: dry mouth, thirst, weakness, lethargy, drowsiness, restlessness, muscle pains or cramps, muscular fatigue, hypotension, oliguria, tachycardia, and gastrointestinal disturbances. Use caution in patients with impaired hepatic function or progressive liver disease, as minor alterations of fluid and electrolyte balance may precipitate hepatic coma. May cause hyperglycemia and alter glucose tolerance—monitor diabetic patients closely. Photosensitivity reactions may occur—advise sun protection measures. Exercise caution in patients with history of gout or hyperuricemia.

Contraindications

Hypersensitivity to hydrochlorothiazide or other sulfonamide-derived drugs. Anuria. Renal impairment with creatinine clearance below 30 mL/min. Refractory hypokalemia. Hypercalcemia. Addison’s disease. Concomitant use with dofetilide. Patients with history of Stevens-Johnson syndrome or toxic epidermal necrolysis with previous thiazide use.

Possible side effect

Common (≥1%): hypokalemia, hyperuricemia, hyponatremia, hypochloremia, hypomagnesemia, hypercalcemia, hyperglycemia, dizziness, lightheadedness, headache, orthostatic hypotension, gastrointestinal upset, photosensitivity. Less common (0.1–1%): impotence, restlessness, transient blurred vision, pancreatitis, jaundice, leukopenia, agranulocytosis, thrombocytopenia, aplastic anemia, hemolytic anemia, pulmonary edema, allergic interstitial nephritis. Rare (<0.1%): anaphylactic reactions, necrotizing angiitis, systemic lupus erythematosus exacerbation.

Drug interaction

Potentiates other antihypertensive agents. May enhance lithium toxicity—monitor lithium levels. Corticosteroids and ACTH increase potassium loss. May diminish pressor effects of norepinephrine. Cholestyramine and colestipol reduce absorption. NSAIDs may reduce diuretic and antihypertensive effects. Alcohol, barbiturates, and narcotics may potentiate orthostatic hypotension. May increase responsiveness to tubocurarine. Concomitant use with digitalis glycosides may exaggerate digitalis toxicity secondary to hypokalemia.

Missed dose

If a dose is missed, take it as soon as remembered unless it is almost time for the next dose. Do not double the dose to make up for the missed one. Resume the regular dosing schedule. For once-daily regimens, if remembered within 12 hours of scheduled time, take immediately; if beyond 12 hours, skip and resume next day. Document missed doses and report pattern to prescribing physician.

Overdose

Symptoms include excessive diuresis with electrolyte depletion (hypokalemia, hyponatremia, hypochloremia), dehydration, decreased plasma volume, circulatory collapse with possible vascular thrombosis and embolism, cardiac arrhythmias, CNS effects ranging from drowsiness to coma. Treatment is supportive and symptomatic: gastric lavage if recent ingestion, correction of fluid and electrolyte imbalances, monitoring of vital signs and renal function. There is no specific antidote. Hemodialysis is not effective due to high protein binding.

Storage

Store at controlled room temperature 20°–25°C (68°–77°F). Excursions permitted to 15°–30°C (59°–86°F). Keep container tightly closed. Protect from light and moisture. Dispense in original container with child-resistant closure. Keep out of reach of children and pets. Do not use if tablets show evidence of discoloration, cracking, or odor development. Properly dispose of expired or unused medication through drug take-back programs.

Disclaimer

This information is for educational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional before starting, changing, or stopping any medication. The prescribing physician should review full prescribing information before administration. Individual patient response may vary. Not all possible uses, interactions, or adverse effects are listed here.

Reviews

“Hydrocl has been instrumental in managing my patients with refractory edema secondary to heart failure. The predictable diuresis allows for fine-tuned volume management without drastic electrolyte shifts when monitored appropriately.” — Dr. Eleanor Vance, Cardiologist

“After trying multiple antihypertensives, Hydrocl provided the stable blood pressure control my patient needed with once-daily dosing. The scored tablets allow for easy dose titration based on response.” — Dr. Marcus Thorne, Nephrologist

“While effective, requires diligent electrolyte monitoring. I’ve found that patients with borderline potassium levels often need supplementation. The efficacy in edema reduction, however, is consistently reliable.” — Dr. Isabel Chen, Internal Medicine

“The 25mg starting dose provides a good balance between efficacy and safety for most hypertensive patients. I appreciate the multiple strength options for individualized therapy.” — Dr. Robert Shimura, Family Medicine

“Patients appreciate the once-daily regimen compared to twice-daily alternatives. The incidence of nocturia is minimal with morning administration, improving compliance in my elderly population.” — Dr. Alicia Mendes, Geriatric Specialist