§ 01 Overview
Overview
The first oral ghrelin-receptor agonist ever approved. Single-dose diagnostic for adult growth hormone deficiency that replaces the more burdensome insulin tolerance test.
FDA-approved December 2017 (Macrilen NDA 205598). Head-to-head vs. insulin tolerance test showed comparable diagnostic performance.
§ 02 Mechanism
Mechanism of action
Macimorelin is an orally active, peptidomimetic GHS-R1a agonist. A single oral dose produces a robust GH pulse within 30–90 minutes; failure to raise GH above a threshold is diagnostic for adult GHD.
- 01Single-dose, oral, outpatient diagnostic for adult GHD
- 02Replaces the insulin tolerance test in many protocols
- 03Well-defined diagnostic threshold
§ 03 Dosing
Dosing protocol
Standard Protocol
- Dose Range
- 0.5 mg/kg as a single diagnostic dose
- Route
- Oral
- Timing
- Fasting, single-use diagnostic
- Frequency
- Single dose
- Cycle
- Diagnostic test only
§ 04 Evidence
Evidence & research
FDA-approved December 2017 (Macrilen NDA 205598). Head-to-head vs. insulin tolerance test showed comparable diagnostic performance.
FDA Status
FDA-approved (Macrilen, 2017); diagnostic indication only.
§ 07 Sourcing
Sourcing & supply
Regulatory status
FDA-approved
This compound has an FDA approval for at least one indication. Brand pharmacy channels exist. Compounding may or may not be available depending on shortage status.
No suppliers in our directory currently stock this compound. For investigational or research-only compounds, legitimate channels may not exist outside clinical trials.
Browse full supplier directory§ 09 Safety
Safety & side effects
Side effects
- 01Dysgeusia (metallic taste)
- 02Headache
- 03QTc prolongation
Contraindications
- 01QTc prolongation risk
- 02Strong CYP3A4 inducers
§ 10 Questions
Macimorelin FAQ
- What is Macimorelin?
- The first oral ghrelin-receptor agonist ever approved. Single-dose diagnostic for adult growth hormone deficiency that replaces the more burdensome insulin tolerance test. Macimorelin is an orally active, peptidomimetic GHS-R1a agonist. A single oral dose produces a robust GH pulse within 30–90 minutes; failure to raise GH above a threshold is diagnostic for adult GHD.
- What is Macimorelin used for?
- Reported uses include single-dose, oral, outpatient diagnostic for adult ghd, replaces the insulin tolerance test in many protocols, and well-defined diagnostic threshold. Evidence strength is rated Established — see the evidence section for detail.
- How is Macimorelin dosed?
- Commonly referenced dosing is 0.5 mg/kg as a single diagnostic dose, typically single dose, administered Oral. This is educational reference only; consult a licensed clinician before use.
- What are the side effects of Macimorelin?
- Commonly reported side effects include dysgeusia (metallic taste), headache, and qtc prolongation. This list is not exhaustive.
- Is Macimorelin legal?
- This compound has an FDA approval for at least one indication. Brand pharmacy channels exist. Compounding may or may not be available depending on shortage status. FDA status: FDA-approved (Macrilen, 2017); diagnostic indication only..
§ 11 References
Selected references
- 01
Garcia — head-to-head vs ITT
JCEM 2018, PMID: 29955892
- 02
FDA Macrilen label
NDA 205598