ACTHAR
Clinical safety rating: caution
Comprehensive clinical and safety monograph for ACTHAR (ACTHAR).
ACTHAR (repository corticotropin injection) is a purified adrenocorticotropic hormone (ACTH) analogue that stimulates the adrenal cortex to release cortisol, corticosterone, and aldosterone. It also has glucocorticoid and mineralocorticoid effects, and is thought to exert anti-inflammatory and immunosuppressive effects through melanocortin receptor activation, independent of adrenal steroid production.
| Metabolism | ACTHAR is a polypeptide (ACTH analogue) that is metabolized by proteolytic degradation in plasma and tissues. Specific CYP enzymes are not involved. The half-life is approximately 15 minutes for ACTH activity, but effects on adrenal steroidogenesis persist longer. |
| Excretion | Primarily renal; <5% unchanged in urine; extensive metabolism via proteolysis. |
| Half-life | 15-20 minutes (intravenous); clinical duration longer due to sustained adrenal stimulation. |
| Protein binding | Low; <30% bound to albumin and corticosteroid-binding globulin. |
| Volume of Distribution | 0.3-0.5 L/kg; distributes primarily into extracellular fluid. |
| Bioavailability | IM: ~80%; SubQ: ~60%; Intranasal: ~10% (gel formulation, variable). |
| Onset of Action | IM: 2-4 hours; IV: 15-30 minutes; SubQ: 4-6 hours. |
| Duration of Action | 8-24 hours; depends on dose and route; single dose often provides 8-12 hours of corticotropic effect. |
ACTHAR (repository corticotropin injection) 80 U/mL; for acute exacerbation of multiple sclerosis: 80-120 U IM daily for 2-3 weeks. For infantile spasms: 150 U/m² IM daily divided twice daily for 2 weeks, then taper.
| Dosage form | INJECTABLE |
| Renal impairment | No specific GFR-based dose modifications established; use with caution in renal impairment due to potential fluid retention and hypertension. |
| Liver impairment | No specific Child-Pugh based modifications; use with caution in hepatic impairment due to potential electrolyte disturbances and fluid retention. |
| Pediatric use | Infantile spasms: 150 U/m² IM daily divided twice daily for 2 weeks, then taper over 2 weeks. Maximum effect often seen at doses up to 150 U/m²/day. |
| Geriatric use | Elderly patients may be more sensitive to corticosteroid effects; start at low end of dosing range and monitor for fluid retention, hypertension, and hyperglycemia. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for ACTHAR (ACTHAR).
| Breastfeeding | Corticosteroids are excreted in breast milk in low amounts; the milk-to-plasma ratio for ACTH-derived corticosteroids is approximately 0.1-0.3. Doses up to 80 mg/day prednisone equivalent are considered compatible with breastfeeding. Monitor infant for adrenal suppression if mother receives high-dose therapy. |
| Teratogenic Risk | First trimester: Corticosteroids are associated with a small increased risk of oral clefts (odds ratio ~3.4); use only if clearly needed. Second and third trimesters: Chronic use may cause fetal adrenal suppression, intrauterine growth restriction, and premature birth. Avoid prolonged high-dose exposure. |
■ FDA Black Box Warning
ACTHAR has no FDA boxed warning.
| Common Effects | Dryness in mouth Constipation Lightheadedness Drowsiness |
| Serious Effects |
["Hypersensitivity to corticotropin or any component of the formulation","Administration of live or live attenuated vaccines (due to immunosuppression)","Congestive heart failure (unless due to acute rheumatic carditis)","Systemic fungal infections","Herpes simplex of the eye","Recent surgery","History of or active peptic ulcer disease","Hypertension (severe or uncontrolled)","Diabetes mellitus (unless used under close supervision)","Osteoporosis","Myasthenia gravis (relative)","Diverticulitis, nonspecific ulcerative colitis, or recent intestinal anastomosis","Renal insufficiency or calculi","Psychoses or severe emotional instability","Cushing's syndrome","Primary adrenocortical insufficiency (relative)"]
| Precautions | ["May mask signs of infection; use with caution in patients with bacterial, fungal, or viral infections.","May cause adrenal suppression; gradual withdrawal after prolonged therapy.","Risk of gastrointestinal perforation, especially in patients with diverticulitis, recent intestinal anastomosis, or peptic ulcer disease.","Can induce hypertension, congestive heart failure, and electrolyte disturbances due to mineralocorticoid effects.","May increase intraocular pressure; use cautiously in glaucoma and cataract patients.","May cause behavioral and mood disturbances, including psychosis.","Live vaccines contraindicated during therapy; killed vaccines may have reduced efficacy.","May exacerbate diabetes mellitus or cause hyperglycemia.","Use in pregnancy only if clearly needed; may cause fetal harm.","Safety and efficacy in children for conditions other than infantile spasms and nephrotic syndrome not established."] |
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| Fetal Monitoring | Monitor maternal blood pressure, blood glucose, and signs of infection. Fetal monitoring includes serial ultrasound for growth restriction, and assessment of fetal adrenal function if chronic therapy is necessary. Consider neonatal adrenal function testing at birth if maternal use continued until delivery. |
| Fertility Effects | No direct adverse effects on fertility reported. However, chronic ACTH use can suppress endogenous HPA axis, potentially causing menstrual irregularities and anovulation due to secondary adrenal insufficiency. Reversible upon dose reduction or discontinuation. |
| Food/Dietary | Avoid excessive salt intake as ACTH can cause fluid retention and hypertension. Maintain a low-sodium diet if recommended by doctor. No specific food interactions; however, grapefruit juice may increase corticosteroid levels, but this is not well-studied with ACTH. Limit alcohol as it may worsen gastrointestinal effects. |
| Clinical Pearls | ACTHAR (repository corticotropin) is a natural adrenocorticotropic hormone (ACTH) preparation used primarily for infantile spasms (West syndrome) and multiple sclerosis exacerbations. It is not equivalent to synthetic ACTH; dosing is in units, not mg. For infantile spasms, typical dose is 150 U/m2/day IM divided twice daily for 2 weeks, then taper. Monitor for hypertension, hyperglycemia, electrolyte disturbances, and immunosuppression. Do not use for routine inflammatory conditions due to risk of HPA axis suppression. Use with caution in patients with diabetes, CHF, or osteoporosis. |
| Patient Advice | This medication is given by injection into a muscle (IM), usually by a healthcare professional or trained caregiver. · Do not stop taking this medication suddenly without consulting your doctor; dose must be tapered to avoid withdrawal symptoms. · Report any signs of infection (fever, sore throat), swelling of legs, unusual weight gain, or mood changes immediately. · May cause increased appetite, insomnia, or irritability, especially in children. · Avoid live vaccines during treatment and for at least 3 months after stopping. · Monitor blood sugar if diabetic; may require dose adjustment of diabetes medications. |