COSYNTROPIN
(koe-sin-troe'pin)
Cortrosyn
Classifications: diagnostic agent
Prototype: Prednisone
Pregnancy Category: C

Availability

0.25 mg injection

Actions

Synthetic polypeptide resembling corticotropin (ACTH) in relation to the first 24 of the 39 amino acids in naturally occurring ACTH. Has less immunologic activity and is associated with less risk of sensitivity than corticotropin.

Therapeutic Effects

In patient with normal adrenocortical function, stimulates adrenal cortex to secrete corticosterone, cortisol (hydrocortisone), several weak androgenic substances, and limited amounts of aldosterone.

Uses

Diagnostic tool to differentiate primary adrenal from secondary (pituitary) adrenocortical insufficiency.

Unlabeled Uses

In patients with normal adrenocortical function for the long-term treatment of chronic inflammatory or degenerative disorders responsive to glucocorticoids.

Contraindications

History of allergic disorders; scleroderma, osteoporosis; systemic fungal infections, ocular herpes simplex; recent surgery; history of or presence of peptic ulcer; CHF; hypertension; adrenocortical insufficiency and adrenocortical hyperfunction; pregnancy (category C), lactation; immunizations, tuberculosis, infections.

Cautious Use

Multiple sclerosis, acute gouty arthritis, mental disturbances, diabetes, abscess, pyrogenic infections, diverticulitis, renal insufficiency, myasthenia gravis, children.

Route & Dosage

Rapid Screening Test
Adult/Child: >2 y: IM/IV 0.25 mg injected over 2 min
Child: <2 y: IM 0.125 mg injected over 2 min; IV 0.125 mg at 0.04 mg/h over 6 h
Neonate: IM/IV 0.015 mg/kg

Administration

Intramuscular

Reconstitute cosyntropin powder by adding 1.1 mL NS (diluent provided by manufacturer) to vial labeled 0.25 mg to provide solution containing 0.25 mg/mL.
Inject deep IM into a large muscle.

Intravenous

IV administration to neonates, infants and children: Verify correct IV concentration and rate of infusion/injection with physician.

PREPARE: Direct: Reconstitute as for IM. IV Infusion: Further dilute in 250–500 mL of D5W or NS.

ADMINISTER: Direct: Give over 2 min. IV Infusion: Give at an approximate rate of 40 mcg/h over 4–6 h.

Reconstituted solutions remain stable 24 h at room temperature or 21 d at 2°–8° C.
Cosyntropin should not be added to blood or to plasma infusions.

Adverse Effects (1%)

Body as a Whole: Mild fever. GI: chronic pancreatitis. Skin: Pruritus.

Diagnostic Test Interference

Cortisone, hydrocortisone, estrogen, spironolactone elevated bilirubin, and presence of free Hgb in plasma may interfere with plasma cortisol determinations.

Interactions

Drug: Cortisone, hydrocortisone can exhibit abnormally high baseline values of cortisol and a decreased response to cosyntropin test.

Pharmacokinetics

Absorption: Plasma cortisol levels double in 15–30 min. Peak: 1 h. Duration: 2–4 h. Distribution: Unknown; does not cross placenta. Metabolism: Unknown.

Nursing Implications

Assessment & Drug Effects

Normal 17-KS levels in men are 10–25 mg/24 h; in women <50 y, 5–15 mg/24 h; and in women >50 y, 4–8 mg/24 h.
Normal 17-OHCS levels in men are 5–12 mg/24 h; in women, 3–10 mg/24 h; in children 8–12 y, <4.5 mg/24 h; in younger children, 1.5 mg/24 h. Levels may be slightly higher in obese or muscular individuals.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug