Inamrinone
Mechanism :
Positive inotrope with direct pulmonary vasodilator (decrease both preload & afterload) activity, which increases cardiac output; these effects result from increases in cellular levels of cAMP as inamrinone inhibits myocardial cAMP phosphodiesterase.
Indication :
Contraindications :
Hypersensitivity to inamrinone, milrinone and bisulfites.
Use with caution in Electrolyte abnormalities, Hypotension, Proarrhythmic effects, Insufficient cardiac filling pressure, Severe aortic or pulmonic valvular disease, Renal impairment, Concurrent use of disopyramide (may cause hypotension).
Dosing :
Load as in adults:
0.75 mg/kg IV over 3-5 minutes, then 3-5 mcg/kg/min IV maintenance infusion (in neonates) and 5-15 mcg/kg/min IV infusion (in children >28 days). Bolus dose may need to be repeated after 30 minutes. Total daily dose should not exceed 10 mg/kg/day. Therapeutic dosage range: 0.5-7 mcg/mL.
Adverse Effect :
Arrhythmia, thrombocytopenia, nausea, hypotension, fever, vomiting, abdominal pain, anorexia.
Interaction :
Anagrelide: Either increases effects of the other by pharmacodynamic synergism.
Milrinone: Either increases effects of the other by pharmacodynamic synergism.
Hepatic Dose :
Hepatotoxicity has occurred rarely. If acute transaminitis occurs along with clinical symptoms due idiosyncratic hypersensitivity reaction, inamrinone should be stopped. If transaminitis is not marked and the patient is asymptomatic, dose adjustment may be based on benefit/risk considerations.