Macimorelin Reference

Plain English

What it is

Macimorelin (brand name Macrilen) is an FDA-approved prescription medicine. It is an oral liquid that doctors give as a one-time test to check whether an adult's body makes enough growth hormone. It works by switching on the same body receptor that the natural hunger hormone ghrelin uses, which briefly nudges the pituitary gland to release growth hormone so the level can be measured.

What people use it for

Its only approved job is a single diagnostic test for growth hormone deficiency in adults. It is not a treatment and not a body or muscle aid. Online discussions sometimes compare it to other oral growth hormone agents, but that comparison can be misleading because it is meant for one-time testing, not ongoing use.

What the science shows

It is studied in adults, and the human prescribing label supports its use as a provocative test for diagnosing growth hormone deficiency. A separate study in children (childhood-onset growth hormone deficiency) has been run, but that use is not FDA-approved.

The catch

This is a prescription medicine given under medical supervision, not something for self-use. The label warns it can prolong the QT interval (an electrical change in the heartbeat) that can raise the risk of dangerous heart rhythms, so it is kept away from other drugs that affect heart rhythm. Certain other medicines can also lower its level in the body and cause a false test result.

Reference summary

Macimorelin is a label-verified oral ghrelin receptor agonist used as a single-dose GH-axis provocative test. pepSmart surfaces label-reference content only.

Regulatory and posture

Categories

Hormonal, GH Release

Aliases

Macrilen, Oral ghrelin agonist diagnostic

Evidence posture

human

Regulatory status

FDA-approved prescription medication (Macrilen). Indicated as a single-dose oral diagnostic for adult growth hormone deficiency. Not a therapeutic; not a body-composition aid.

Content review status

label verified

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