How do I take Macrilen (macimorelin)?

This medication is an oral solution that you'll drink by mouth. Your provider will prepare and calculate your dose of Macrilen (macimorelin) based on your weight. You'll need to fast for at least 8 hours before drinking Macrilen (macimorelin). On the day of your adult growth hormone deficiency test, you'll drink the Macrilen (macimorelin) solution all at once in 30 seconds. After this, you'll have a series of blood draws done to check your GH levels. Ask your provider for more information on what to expect during your test.

How do I prepare for the test to check for my growth hormone levels?

Make sure you don't eat or drink anything, except for water, for at least 8 hours before your test. Your treatment for GH will need to be stopped at least one week before your test with Macrilen (macimorelin). Discuss with your provider what other medications you need to stop taking in advance. Certain medications (e.g. growth hormone therapy, thyroid medications) can affect your hormones and alter your test results.

What are some side effects of Macrilen (macimorelin)?

Common side effects with Macrilen (macimorelin) include changes in your taste, dizziness, headache, tiredness, nausea, and hunger. Other less common side effects can include diarrhea, feeling hot, and sweating a lot. Though more rare, Macrilen (macimorelin) can also affect your heartbeat and cause a serious heart problem called [QT prolongation](https://www.goodrx.com/hcp-articles/providers/qt-prolongation-risk-assessment). Speak with your provider before going in for your test if you are taking other medications that can affect your heart.

Macrilen

macimorelin

Used for Growth Hormone Deficiency

Macrilen (macimorelin) is a medication used by healthcare providers to test for adult growth hormone deficiency. This is a test to check whether your body makes enough growth hormone (GH). Macrilen (macimorelin) is given as an oral solution that you drink, but you'll need to get several blood draws afterwards to measure your GH levels.

Reviewed by:

Yen Nguyen, PharmD

Allison Gourley, PharmD

Last reviewed on July 12, 2022

What is Macrilen (macimorelin)?

What is Macrilen (macimorelin) used for?

Diagnosis of adult growth hormone deficiency (AGHD)

Drug facts

Common Brands	Macrilen
Drug Class	Growth hormone releasing factor agonist
Controlled Substance Classification	Not a controlled medication
Generic Status	No lower-cost generic available
Availability	Prescription only

Common Brands

Macrilen

Drug Class

Growth hormone releasing factor agonist

Controlled Substance Classification

Not a controlled medication

Generic Status

No lower-cost generic available

Availability

Prescription only

Common questions about Macrilen

Macrilen is a medication that your provider gives you to take so they can test to see if you are low on growth hormone (GH). GH is important for proper growth and plays a major role in many processes in your body. In adults, low levels of GH can affect the nerves, brain, heart, muscles, metabolism, and bones. Macrilen works by telling your body to release more GH.

This medication is an oral solution that you'll drink by mouth. Your provider will prepare and calculate your dose of Macrilen based on your weight. You'll need to fast for at least 8 hours before drinking Macrilen. On the day of your adult growth hormone deficiency test, you'll drink the Macrilen solution all at once in 30 seconds. After this, you'll have a series of blood draws done to check your GH levels. Ask your provider for more information on what to expect during your test.

Make sure you don't eat or drink anything, except for water, for at least 8 hours before your test. Your treatment for GH will need to be stopped at least one week before your test with Macrilen. Discuss with your provider what other medications you need to stop taking in advance. Certain medications (e.g. growth hormone therapy, thyroid medications) can affect your hormones and alter your test results.

The entire testing process can take at least 2 hours, so please be prepared. Once the Macrilen solution is given to you, drink the entire amount within 30 seconds. After taking your medication, you will be monitored for the remainder of the test. Your provider will take your blood sample at 30 minutes, 45 minutes, 60 minutes, and 90 minutes after you drink your Macrilen solution.

Common side effects with Macrilen include changes in your taste, dizziness, headache, tiredness, nausea, and hunger. Other less common side effects can include diarrhea, feeling hot, and sweating a lot. Though more rare, Macrilen can also affect your heartbeat and cause a serious heart problem called QT prolongation. Speak with your provider before going in for your test if you are taking other medications that can affect your heart.

It's not known if Macrilen can cause harm to your unborn baby or pass into your breastmilk. Speak to your provider if you are pregnant or breastfeeding, and they can help you determine if you can take Macrilen for your GH deficiency test.