Overview
11 Description Cosyntropin is an adrenocorticotropic hormone (ACTH). Cosyntropin is synthetic beta 1 - 24 corticotropin, a synthetic subunit of ACTH. It is an open chain polypeptide containing, the first 24 of the 39 amino acids of natural ACTH in sequence from N terminal. The sequence of amino acids in the 1 - 24 compound is as follows: The empirical formula is C 136 H 210 N 40 O 31 S with a...
Mechanism of Action
12 Clinical Pharmacology 12.1 Mechanism of Action Cosyntropin exhibits the full corticosteroidogenic activity of natural ACTH. Various studies have shown that the biologic activity of ACTH resides in the N-terminal portion of the molecule and that the 1-20 amino acid residue is the minimal sequence retaining full activity. Partial or complete loss of activity is noted with progressive shortening of the chain beyond 20 amino acid residues. For example, the decrement from 20 to 19 results in a 70% loss of potency. The pharmacologic profile of CORTROSYN is similar to that of purified natural ACTH. It has been established that 0.25 mg of CORTROSYN will stimulate the adrenal cortex maximally and to the same extent as 25 units of natural ACTH.
Indications
- 1 Indications and Usage CORTROSYN is indicated, in combination with other diagnostic tests, for use as a diagnostic agent in the screening of adrenocortical insufficiency in adults and pediatric patients. CORTROSYN is an adrenocorticotropin hormone indicated, in combination with other diagnostic tests, for use as a diagnostic agent in the screening of adrenocortical insufficiency in adults and pediatric patients. (1)
Common Doses
- 0.25 mg
- 1 mL
- 18 mcg
- 0.125 mg
Dosage
2 Dosage and Administration 2.1 Important Information Before Conducting CORTROSYN TESTING In general, stop glucocorticoids and spironolactone on the day of CORTROSYN testing. However, long-acting glucocorticoids may need to be stopped for a longer period before CORTROSYN testing [see Warnings and Precautions (5.2), Drug Interactions (7)]. Stop estrogen-containing drugs four to six weeks before CORTROSYN testing [see Warnings and Precautions (5.2), Drug Interactions (7)]. 2.2 Recommended Dose for Adults The recommended dose of CORTROSYN in adults is 0.
Contraindications
- 4 Contraindications CORTROSYN is contraindicated in patients with a history of hypersensitivity to cosyntropin or to any excipients of CORTROSYN. Reactions have included anaphylaxis [see Warnings and Precautions (5.1)]. CORTROSYN is contraindicated in patients with a history of hypersensitivity to cosyntropin or to any excipients of CORTROSYN. Reactions have included anaphylaxis. (4, 5.1)
Side Effects
- 6 Adverse Reactions Because adverse reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. The following adverse reactions have been identified during post approval use of CORTROSYN: anaphylactic reaction bradycardia tachycardia hypertension peripheral edema rash Most common adverse reactions are: anaphylactic reaction, bradycardia, tachycardia, hypertension, peripheral edema, and rash (6) To report SUSPECTED ADVERSE REACTIONS, contact Amphastar Pharmaceuticals,...
Interactions
- 7 Drug Interactions 7.1 Drug Effects on Plasma Cortisol Levels Accuracy of the test results can be affected by concomitant medications. Plasma cortisol levels and subsequent diagnosis of adrenocortical insufficiency following CORTROSYN administration may be inaccurate if patients are on certain medications because of their effect on cortisol or cortisol binding globulin levels [see Dosage and Administration (2.1) and Warnings and Precautions (5.2)]. Glucocorticoids and spironolactone: May falsely elevate plasma cortisol levels. Stop these drugs on the day of CORTROSYN testing.