Dolasetron mesylate
Dolasetron mesylate (Anzemet)
Dolasetron mesylate
(dohl- AH-seh-tron)
Pregnancy Category: B Anzemet (Rx)

Classification: Antinauseant/antiemetic, serotonin 5-HT ₃ antagonist

Action/Kinetics: Selective serotonin 5-HT ₃ antagonist that prevents N&V; by inhibiting released serotonin from combining with receptors on vagal efferents that initiate vomiting reflex. May also cause acute, usually reversible, PR and QT _c prolongation and QRS widening, perhaps due to blockade of sodium channels by active metabolite of dolasetron. Well absorbed from GI tract. Metabolized to active hydrodolasetron: peak plasma levels: 1 hr; t 1/2: 8.1 hr. Food does not affect bioavailability. Hydrodolasetron is excreted through urine and feces. Is eliminated more quickly in children than in adults.

Uses: Prevention of N&V; associated with moderately-emetogenic cancer chemotherapy (initially and repeat courses). Prevention of postoperative N&V.;

Special Concerns: Use with caution during lactation and in those who have or may develop prolongation of cardiac conduction intervals, including QT _c. These include clients with hypokalemia or hypomagnesemia, those taking diuretics with potential for electrolyte abnormalities, in congenital QT syndrome, those taking anti-arrhythmic drugs or other drugs which lead to QT prolongation, and cumulative high dose anthracycline therapy. Safety and efficacy in children less than 2 years of age have not been determined.

Side Effects: Chemotherapy clients. Headache, fatigue, diarrhea, bradycardia, dizziness, pain, tachycardia, dyspepsia, chills, shivering. Postoperative clients. Headache, hypotension, dizziness, fever, pruritus, oliguria, hypertension, tachycardia. Chemotherapy or postoperative clients. C V: Hypotension, edema, peripheral edema, peripheral ischemia, thrombophlebitis, phlebitis. GI: Constipation, dyspepsia, abdominal pain, anorexia, pancreatitis, taste perversion. CNS: Flushing, vertigo, paresthesia, tremor, ataxia, twitching, agitation, sleep disorder, depersonalization, confusion, anxiety, abnormal dreaming. Dermatologic: Rash, increased sweating. Hematologic: Hematuria, epistaxis, anemia, purpura, hematoma, thrombocytopenia. Hypersensitivity: Rarely, anaphylaxis facial edema, urticaria. Musculoskeletal: Myalgia, arthralgia. Respiratory: Dyspnea, bronchospasm. GU: Dysuria, polyuria, acute renal failure. Ophthalmic: Abnormal vision, photophobia. Miscellaneous: Tinnitus.

Laboratory Test Alterations: PTT, AST, ALT, alkaline phosphatase. Prolonged prothrombin time.

Drug Interactions: Possible interaction with drugs that the prolong QT _c interval.

How Supplied: Injection: 20 mg/mL; Tablet: 50 mg, 100 mg

Dosage
?Tablets Prevention of N&V; during chemotherapy.
Adults: 100 mg within 1 hr before chemotherapy. Children, 2 to 16 years: 1.8 mg/kg within 1 hr before chemotherapy, up to a maximum of 100 mg.
Prevention of postoperative N&V.;
Adults: 100 mg within 2 hr before surgery. Children, 2 to 16 years: 1.2 mg/kg within 2 hr before surgery, up to a maximum of 100 mg.
?IV Prevention of N&V; during chemotherapy.
Adults: 1.8 mg/kg as a single dose about 30 min before chemotherapy. Alternatively, a fixed dose of 100 mg can be given over 30 seconds. Children, 2 to 16 years: 1.8 mg/kg as a single dose about 30 min before chemotherapy, up to a maximum of 100 mg.
Prevention of postoperative N&V.;
Adults: 12.5 mg given as a single dose. Children, 2 to 16 years: 0.35 mg/kg, up to a maximum of 12.5 mg. For adults and children, give about 15 min before cessation of anesthesia or as soon as nausea and vomiting presents.

Note: For children, injection may be mixed with apple or apple-grape juice and used for oral dosing. When injection is used PO, recommended dose for prevention of cancer chemotherapy N&V; is 1.8 mg/kg (up to a maximum of 100 mg) and dose for prevention of postoperative N&V; is 1.2 mg/kg (up to a maximum of 100 mg). Diluted injection may be kept up to 2 hr at room temperature before use.