PRESITON

COMPOSITION:

Presiton-25:

Each tablet contains: Spironolactone USP 25 mg

Presiton -50: 

Each tablet contains: Spironolactone USP   50 mg

Presiton -100: 

Each tablet contains: Spironolactone USP 100 mg

CLINICAL PHARMACOLOGY:

Mechanism of Action: 

Spironolactone is a specific pharmacologic antagonist of aldosterone, acting primarily through competitive binding of receptors at the aldosterone-dependent sodium-potassium exchange site in the distal convoluted renal tubule. Spironolactone causes increased amounts of sodium and water to be excreted, while potassium is retained. Spironolactone acts both as a diuretic and as an antihypertensive drug by this mechanism. It may be given alone or with other diuretic agents which act more proximally in the renal tubule.

Pharmacokinetics:

Absorption: Spironolactone is rapidly absorbed after oral administration, with peak plasma concentration occurring within 1–3 hours.

Distribution: It is widely distributed in body tissues, with a volume of distribution of approximately 3–5 L/kg and is 90% protein bound.

Metabolism:Spironolactone is extensively metabolized in the liver to active metabolites, primarily canrenone, which contribute to its therapeutic effects.

Elimination:It is eliminated primarily through the urine, with a half-life of around 1.4 hours for spironolactone and 13–24 hours for its metabolites; approximately 10% is excreted unchanged.

INDICATIONS AND USAGE: 

Spironolactone is indicated for primary hyperaldosteronism, edematous conditions (e.g., heart failure, cirrhosis, nephrotic syndrome), essential hypertension, hypokalemia, and severe heart failure (NYHA class III-IV) to improve survival and reduce hospitalizations.

DOSAGE AND ADMINISTRATION:

Spironolactone can be taken with or without food, consistently. For heart failure, start with 25 mg daily for normal potassium levels and eGFR >50 mL/min, with adjustments as needed. For hypertension, the initial dose is 25–100 mg daily, adjusted every two weeks, with doses above 100 mg generally ineffective. For edema, start with 100 mg daily, increasing if necessary after 5 days.

WARNINGS AND PRECAUTIONS: 

Warnings:

Hyperkalemia: Monitor serum potassium within one week of initiation and regularly thereafter.

Hypotension and Worsening Renal Function: Periodically monitor volume status and renal function.

Precautions:

Electrolyte and Metabolic Abnormalities: Periodically monitor serum electrolytes, uric acid, and blood glucose.

Gynecomastia: Spironolactone can cause gynecomastia.

ADVERSE REACTIONS:

Clinically significant adverse reactions of spironolactone include hyperkalemia, hypotension, worsening renal function, electrolyte and metabolic abnormalities, gynecomastia, and impaired neurological function or coma in patients with hepatic impairment, cirrhosis, and ascites.

DRUG INTERACTIONS:

Concomitant use of spironolactone with potassium supplements or drugs that increase potassium can lead to severe hyperkalemia. Potassium supplementation should be discontinued in heart failure patients starting spironolactone, and serum potassium should be monitored when ACE inhibitors or ARBs are altered. Drugs that can increase potassium include ACE inhibitors, ARBs, NSAIDs, heparin, and trimethoprim.

USE IN SPECIFIC POPULATIONS:

Pregnancy: Based on animal data, ALDACTONE may affect sex differentiation of the male during embryogenesis.

Nursing Mothers: Spironolactone is not present in breastmilk; however, limited data from a lactating woman at 17 days postpartum reports the presence of the active metabolite, canrenone, in human breast milk in low amounts that are expected to be clinically inconsequential. In this case, there were no adverse effects reported for the breastfed infant after short term exposure to spironolactone; however, long term effects on a breastfed infant are unknown. 

Pediatric Use: Safety and effectiveness in pediatric patients have not been established.

Geriatric Use: Spironolactone is substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function.

CONTRAINDICATIONS: 

Spironolactone is contraindicated in patients with hyperkalemia, Addison's disease, and those using eplerenone concurrently

OVERDOSAGE: 

Acute spironolactone overdose may cause symptoms like drowsiness, rash, nausea, vomiting, dizziness, and diarrhea, with rare instances of hyponatremia, hyperkalemia, or hepatic coma in severe liver disease. Treatment involves supportive care, including hydration, electrolyte balance, and discontinuation of spironolactone in patients with renal impairment.

STORAGE:

Store below 30°C protected from light and moisture. 

PRESENTATION:

 Box containing 10 strips of 10 tablets.