ACTH

Corticotrophin, Corticotropin

Mechanism :

ACTH is synthesised from pro-opiomelanocortin (POMC) and secreted from corticotropes in the anterior lobe of the pituitary gland in response to the hormone corticotropin-releasing hormone (CRH) released by the hypothalamus.

Indication :

• Infantile spasms (West syndrome)
• Anti-inflammatory/immunosuppressant
• Infantile myoclonic seizures
• Diagnostic- adrenocortical deficiency and myasthenia gravis

Contraindications :

A history of a previous adverse reaction to ACTH. Scleroderma, osteoporosis, systemic fungal infections, ocular herpes simplex, peptic ulcer and hypertension.

Dosing :

For diagnostic testing of adrenal function:

<2 years old: 0.125 mg IV/IM.

>2 years old: 0.25 to 0.75 mg IV/IM. Can be given as IV infusion 0.25 mg in dextrose 5% in water or saline 0.9% administered at 0.04 mg/hour over 6 hours.

For infantile spasms:

Infants and Children <2 years: IM: 75 units/m²/dose twice daily for 2 weeks, followed by gradual tapering over 2 weeks (30 units/m²/dose IM once daily in the morning for 3 days, followed by 15 units/m²/dose IM once daily in the morning for 3 days, followed by 10 units/m²/dose once daily in the morning for 3 days and 10 units/m²/dose IM every other morning for 6 days).

For immunosuppression/anti-inflammatory:

0.8 units/kg/day IM or 25 units/m²/day in divided doses every 12-24 hours.

Adverse Effect :

Wheal with erythema at the injection site, anaphylactic reactions, infections, systemic adrenal suppression leading to subcapsular cataract, osteoporosis, glaucoma and peptic ulcers, bradycardia, tachycardia, hypertension, peripheral edema, psychosis, striae, muscle weakness, cardiomegaly, necrotizing arteritis, growth failure, pancreatitis, glaucoma.

Interaction :

Corticotropin may accentuate the electrolyte loss associated with diuretic therapy.

Hepatic Dose :