Adult: Alternative to corticosteroids for short-term therapy of cases in patients who are intolerant to oral glucocorticoids: As long-acting depot: Initially, 1 mg daily, or 1 mg 12 hourly (in acute cases). Once acute symptoms are controlled or adequate response is achieved, may continue treatment at reduced doses of 0.5-1 mg every 2-3 days or 1 mg once weekly. Child: As long-acting depot: 3-<5 years Initially, 0.25-0.5 mg daily. Maintenance: 0.25-0.5 mg every 2-8 days; 5-12 years Initially, 0.25-1 mg daily. Maintenance: 0.25-1 mg every 2-8 days.
Parenteral Diagnostic test for investigation of adrenocortical insufficiency
Adult: 30-minute diagnostic test: As conventional preparation: 0.25 mg as a single dose via IV inj over 2 minutes or IM inj, with plasma-cortisol levels measured immediately before and exactly 30 minutes after the inj. If there is a post-inj rise in plasma cortisol levels of at least 200 nmol/L (70 mcg/L), the adrenocortical function may be regarded as normal. Doses may be given via IV infusion over 6 hours when greater cortisol stimulation is necessary. 5-hour diagnostic test: As long-acting depot (if inconclusive results with conventional preparation or to determine adrenal cortex functional reserve): 1 mg as a single IM inj dose, with plasma cortisol levels measured immediately before and exactly 0.5, 1, 2, 3, 4, and 5 hours after the inj. If post-inj rise in plasma cortisol levels doubles in the 1st hour then continues to rise steadily, the adrenocortical function is normal. For the differentiation between primary and secondary adrenocortical insufficiency, the depot preparation may be used as a 3-day test. Refer to detailed product guideline for further instructions on testing. Child: 30-minute diagnostic test: As conventional preparation: Max: 0.25 mg/1.73 m2 as a single dose via IV inj over 2 minutes. Consider detailed product or local guidelines for specific dosage requirements.
Special Patient Group
Patient undergoing therapy for diabetes mellitus or hypertension: Long-acting depot: Dosage adjustments may be required.
IV/IM Powder for inj (for diagnostic use): IM: Reconstitute vial labelled as 0.25 mg with 1 mL of 0.9% NaCl. IV inj: Further dilute the reconstituted solution for IM inj in 0.9% NaCl to a total volume of 2-5 mL. IV infusion: Mix 0.25 mg dose in 0.9% NaCl or 5% dextrose in water.
Patient with active infectious or systemic disease; latent TB or amoebiasis, reduced immune response, hypertension, thromboembolic tendencies, ocular herpes simplex, cataracts, glaucoma, diabetes mellitus, gastrointestinal disease (e.g. nonspecific ulcerative colitis, recent intestinal anastomosis, diverticulitis), osteoporosis, myasthenia gravis, liver cirrhosis, hypothyroidism. Patient with critical illness, nephrotic syndrome, those receiving oral contraceptives, hydrocortisone, cortisone or spironolactone, or have previously undergone operation may have an inaccurate result of plasma cortisol levels; use alternative parameters for assessment. Patient subjected to stress conditions (e.g. trauma, surgery, illness). Concomitant administration with live vaccines. Renal and hepatic impairment. Children. Pregnancy and lactation.
Significant: Hypersensitivity reactions (e.g. marked redness and pain at the inj site, urticaria, pruritus, severe malaise or dyspnoea, flushing), psychological disturbances (e.g. euphoria, insomnia, mood swings, personality changes, severe depression, frank psychotic manifestations); increased intraocular pressure, ocular effects with prolonged use (e.g. corneal perforation, glaucoma, cataracts); salt and water retention, activation of latent TB or amoebiasis. Cardiac disorders: Bradycardia, tachycardia. Ear and labyrinth disorders: Vertigo. Endocrine disorders: Adrenal haemorrhage, Cushing’s syndrome, secondary adrenocortical and pituitary unresponsiveness (particularly during stress); growth retardation in children. Gastrointestinal disorders: Pancreatitis, peptic ulcer with perforation and haemorrhage, oesophagitis ulcerative, abdominal distension. General disorders and administration site conditions: Impaired healing. Infections and infestations: Abscess. Immune system disorders: Increased infection susceptibility. Investigations: Increased weight. Metabolism and nutrition disorders: Latent diabetes mellitus, decreased carbohydrate tolerance, hyperglycaemia, hypokalaemia, Ca deficiency, increased appetite, hypokalaemic alkalosis, peripheral oedema. Musculoskeletal and connective tissue disorders: Osteoporosis, myopathy, pathological fracture of long bones. Nervous system disorders: Convulsion, headache. Reproductive system and breast disorders: Irregular menstruation. Skin and subcutaneous tissue disorders: Hirsutism, rash, skin atrophy. Vascular disorders: Hypertension, necrotising vasculitis, thromboembolism.
Monitor for signs or symptoms of hypersensitivity approx 1 hour after administration. For the diagnosis of adrenocortical insufficiency: Assess plasma cortisol prior to and 4-6 hours after inj. For therapeutic (prolonged) use: Monitor blood pressure, weight, urinalysis, glucose, electrolytes; signs and symptoms of infection, cataract, intraocular pressure, bone mass density, growth and ECG in children. May consider routine eye exam.
Symptoms: Fluid retention, Cushing’s syndrome. Management: Symptomatic treatment. May temporarily withdraw, give in lower doses, or prolong the interval between injections of tetracosactide.
May enhance the hepatotoxic effects of valproate (particularly in children), phenytoin, clonazepam, nitrazepam, phenobarbital, primidone. Increased total cortisol levels with synthetic estrogens thus may diminish the diagnostic effect of tetracosactide. May potentiate the electrolyte loss with diuretics.
May suppress reactions to skin tests.
Description: Tetracosactide is a synthetic polypeptide that stimulates the adrenal cortex to secrete adrenal steroids (including hydrocortisone, cortisone), androgenic substances, and to a lesser extent, aldosterone.
Synonyms: tetracosactrin, cosyntropin. Onset: Increased plasma cortisol concentrations: Within 5 minutes. Duration: 12 hours (IM). Pharmacokinetics: Absorption: Time to peak plasma concentration: Approx 1 hour. Distribution: Rapidly distributed particularly in the adrenals and kidneys. Volume of distribution: Approx 0.4 L/kg. Metabolism: Metabolised by serum endopeptidases into inactive oligopeptides, then by aminopeptidases into free amino acids. Excretion: IV: Via urine (95-100%). Elimination half-life: 3 phases: Approx 7 minutes (range: approx 0-1 hour), 37 minutes (range: 1-2 hours), 3 hours.
Powder for inj: Store between 20-25°C. Solution/suspension for inj: Store between 2-8°C. Protect from light.