Indications
Vaptan Tablet is used for:
Hyponatremia, Polycystic Kidney Disease
Adult Dose
Oral
Hyponatraemia
Adult: In patient with hypervolaemic or euvolaemic cases associated with Syndrome of Inappropriate Antidiuretic Hormone (SIADH): Initially, 15 mg once daily, increase to 30 mg once daily after 24 hours.
Dose may be adjusted up to max 60 mg once daily to achieve desired response.
Max treatment duration: 30 days.
Autosomal dominant polycystic kidney disease (ADPKD)
Adult: Initially, 60 mg daily in 2 divided doses (45 mg before breakfast and 15 mg after 8 hours).
Increase at weekly interval to 90 mg daily in 2 divided doses (60 mg before breakfast and 30 mg after 8 hours up to target dose 120 mg daily in 2 divided doses (90 mg before breakfast and 30 mg after 8 hours).
Reduce dose, if needed according to tolerability.
Hepatic impairment
Moderate and severe hepatic impairment do not affect exposure to tolvaptan to a clinically relevant extent
Underlying liver disease: Avoid use
Child Dose
Renal Dose
Renal impairment
CrCl 10-79 mL/min: No dosage adjustment required
CrCl <10 mL or dialysis: Not recommended; drug effects on serum sodium levels are likely lost at very low levels of renal function
Anuria: Contraindicated; no benefit expected
Administration
May be taken with or without food. Avoid grapefruit juice.
Contra Indications
Anuria, volume depletion, hypovolaemic hyponatraemia, hypernatraemia, elevated liver enzymes, liver disease (e.g. cirrhosis), inability to perceive or respond to thirst.
Precautions
Patient with fluid restriction, urinary outflow obstruction (e.g. prostatic hypertrophy, micturition impairment), risk for demyelination syndromes (e.g. alcoholism or malnutrition), diabetes mellitus. Hepatic and renal impairment (CrCl <10 mL/min). Pregnancy and lactation. Not indicated for urgent treatment of hyponatraemia.
Pregnancy-Lactation
Pregnancy
Available data are insufficient to determine if there is a drug-associated risk of adverse developmental outcomes
Animal studies
In embryo-fetal development studies, pregnant rats and rabbits received oral tolvaptan during organogenesis
At maternally nontoxic doses, tolvaptan did not cause any developmental toxicity in rats or in rabbits at exposures approximately 4- and 1-times, respectively, the human exposure at the maximum recommended human dose (MRHD) of 90/30 mg; however, effects on embryo-fetal development occurred in both species at maternally toxic doses
Lactation
Data are not available on the presence of tolvaptan in human milk, the effects on the breastfed infant, or the effects on milk production
Tolvaptan is present in rat milk
Because of the potential for serious adverse reactions, including liver toxicity, electrolyte abnormalities (eg, hypernatremia), hypotension, and volume depletion in breastfed infants, advise women not to breastfeed during treatment
Interactions
Increased plasma concentration with CYP3A4 inhibitors (e.g. ketoconazole, ritonavir, clarithromycin, diltiazem). Decreased plasma concentration with CYP3A4 inducers (e.g. rifampicin, barbiturates). May increase plasma concentration and cardiac effects of digoxin. May diminish therapeutic effect of desmopressin.
Side Effects
Side effects of Tolvaptan :
Significant: Hyperuricaemia, gout, polydipsia, polyuria, hypovolaemia, dehydration, hyperkalaemia, nocturia, pollakiuria, hyperglycaemia, increased ALT/AST, bilirubin. Rarely, anaphylaxis.
Gastrointestinal disorders: Nausea, dry mouth, constipation, diarrhoea.
General disorders and administration site conditions: Malaise, fever, weakness.
Investigations: Increased creatinine.
Metabolism and nutrition disorders: Hypoglycaemia, decreased appetite, hypernatraemia.
Nervous system disorders: Headache, dizziness.
Skin and subcutaneous tissue disorders: Pruritus, ecchymosis.
Vascular disorders: Syncope, orthostatic hypotension.
Potentially Fatal: Osmotic demyelination, hepatotoxicity.
Mode of Action
Tolvaptan is a selective vasopressin V2-receptor antagonist. It blocks the binding of arginine vasopressin (AVP) at the V2-receptor of the distal portions of the nephrons. This leads to increased urine output resulting to increased water diuresis without electrolyte loss, restoration of normal serum Na concentrations, and decreased urine osmolality.
Note
Vaptan 15mg Tablet generic name is Tolvaptan. Vaptan 15mg Tablet is manufactured by Popular Pharmaceuticals Ltd.Vaptan is availble in all over Bangladesh.
Mes BD drug index information on Vaptan Tablet is not intended for diagnosis, medical advice or treatment; neither intended to be a substitute for the exercise of professional judgment.