Macimorelin
Medically reviewed by Drugs.com. Last updated on Jan 31, 2025.
Pronunciation
(ma si moe REL in)
Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Packet, Oral:
Macrilen: 60 mg (1 ea) [contains saccharin sodium]
Brand Names: U.S.
- Macrilen
Pharmacologic Category
- Diagnostic Agent
- Growth Hormone Secretagogue Receptor Agonist
Pharmacology
Stimulates GH release by activating GH secretagogue receptors in the pituitary and hypothalamus.
Metabolism
Hepatic via CYP3A4
Time to Peak
0.5 to 1.5 hours
Half-Life Elimination
4.1 hours
Use: Labeled Indications
Diagnostic use: Growth hormone deficiency: Diagnosis of adult growth hormone deficiency.
Limitations of use: The safety and diagnostic performance has not been established for patients with BMI >40 kg/m2.
Contraindications
There are no contraindications listed in the manufacturer's labeling
Dosing: Adult
Diagnostic use: Growth hormone deficiency: Note: Correct other pituitary hormone deficiencies prior to administration (AACE/ACE [Yuen 2019]): Oral:
BMI ≤40 kg/m2: 0.5 mg/kg as single dose.
BMI >40 kg/m2: Dose has not been established.
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Dosing: Geriatric
Refer to adult dosing.
Reconstitution
After determining dosage and number of pouches needed, dissolve entire contents of each pouch with 120 mL of water (final concentration equals 0.5 mg/1 mL). Stir solution gently for about 2 to 3 minutes (a small amount of undissolved particles will remain). Transfer volume needed for dose using a syringe (without needle) graduated in mL into a drinking glass.
Administration
Oral: Patient must drink entire dose within 30 seconds after fasting for at least 8 hours.
Storage
Store pouches under refrigeration at 2°C to 8°C (36°F to 46°F). Solution must be used within 30 minutes after preparation. Discard unused portion.
Drug Interactions
Aspirin: May diminish the diagnostic effect of Macimorelin. Avoid combination
Atropine (Systemic): May diminish the diagnostic effect of Macimorelin. Avoid combination
Bosentan: May diminish the diagnostic effect of Macimorelin. Monitor therapy
CloNIDine: May diminish the diagnostic effect of Macimorelin. Avoid combination
Corticosteroids (Systemic): May diminish the diagnostic effect of Macimorelin. Avoid combination
CYP3A4 Inducers (Moderate): May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy
CYP3A4 Inducers (Strong): May decrease the serum concentration of Macimorelin. Avoid combination
Dabrafenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Seek alternatives to concomitant therapy when possible. If concomitant therapy cannot be avoided, monitor for reduced clinical effects of the CYP3A4 substrate. Consider therapy modification
Deferasirox: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy
Efavirenz: May diminish the diagnostic effect of Macimorelin. Monitor therapy
Erdafitinib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy
Etravirine: May diminish the diagnostic effect of Macimorelin. Monitor therapy
Haloperidol: QT-prolonging Agents (Indeterminate Risk - Avoid) may enhance the QTc-prolonging effect of Haloperidol. Monitor therapy
Insulins: May diminish the diagnostic effect of Macimorelin. Avoid combination
Ivosidenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy
Levodopa-Containing Products: May diminish the diagnostic effect of Macimorelin. Avoid combination
Modafinil: May diminish the diagnostic effect of Macimorelin. Monitor therapy
Nonsteroidal Anti-Inflammatory Agents: May diminish the diagnostic effect of Macimorelin. Avoid combination
Products that Affect Growth Hormone: May diminish the diagnostic effect of Macimorelin. Avoid combination
Propylthiouracil: May diminish the diagnostic effect of Macimorelin. Avoid combination
QT-prolonging Agents (Highest Risk): QT-prolonging Agents (Indeterminate Risk - Avoid) may enhance the QTc-prolonging effect of QT-prolonging Agents (Highest Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Monitor therapy
Sarilumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy
Siltuximab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy
Somatostatin Analogs: May diminish the diagnostic effect of Macimorelin. Avoid combination
St John's Wort: May decrease the serum concentration of Macimorelin. Avoid combination
Tocilizumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy
Adverse Reactions
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.
1% to 10%:
Cardiovascular: Sinus bradycardia (1%)
Central nervous system: Dizziness (4%), fatigue (4%), headache (4%), feeling hot (1%)
Dermatologic: Hyperhidrosis (1%)
Gastrointestinal: Dysgeusia (5%), hunger (3%), nausea (3%), diarrhea (2%)
Respiratory: Upper respiratory tract infection (2%), nasopharyngitis (1%)
Frequency not defined:
Cardiovascular: Prolonged QT interval on ECG
Related/similar drugs
Warnings/Precautions
Concerns related to adverse effects:
• QT prolongation: Prolongation of the QTc interval (~11 msec) has been observed in clinical trials at doses 2- and 4-times the recommended dosage; avoid concurrent use with other agents known to prolong the QT interval.
Disease-related concerns:
• Endocrine disorders: Correct other pituitary hormone deficiencies prior to administration.
• Hypothalamic disease: Growth hormone deficiency due to hypothalamic lesion may not be detected early in the disease process; macimorelin stimulates release of stored growth hormone from the anterior pituitary, which may lead to false negative result. Repeat testing may be necessary.
Other warnings/precautions:
• Appropriate use: Discontinue growth hormone therapy ≥1 week prior to administration.
Monitoring Parameters
Serum growth hormone at 30, 45, 60, and 90 minutes following administration
Pregnancy Considerations
Animal reproduction studies have not been conducted.
Patient Education
What is this drug used for?
• It is used to test for growth hormone deficiency.
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
• Fast heartbeat
• Abnormal heartbeat
• Passing out
• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.
Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.
More about macimorelin
- Check interactions
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- Side effects
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- During pregnancy
- Drug class: growth hormones
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