Drug General Information (ID: DDI16LKD5E)
Drug Name			Methadone		Drug Info		Relugolix		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Analgesics				Gonadotropin-Releasing Hormone Antagonists
Structure

Mechanism of Methadone-Relugolix Interaction (Severity Level: Major)
Increased risk of prolong QT interval Click to Show/Hide Mechanism Graph
Drug Name		Methadone				Relugolix
Mechanism		Prolong QT interval				Prolong QT interval
Key Mechanism Factor 1
		Factor Name		QT interval
		Factor Description		Long QT syndrome is a heart signaling disorder that can cause a fast, chaotic heartbeat (arrhythmia). Many people may not exhibit symptoms, and usually the condition is detected during routine medical tests. In others, the most common symptoms include: sudden fainting, palpitations, dizziness, seizures, sudden death.
Mechanism Description		Increased risk of prolong QT interval by the combination of Methadone and Relugolix

Recommended Action
Management		Caution is recommended if methadone is used in combination with other drugs that can prolong the QT interval, particularly in the setting of chronic pain management or methadone maintenance for opioid dependency where high dosages may be employed. Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope. If taking drugs that also cause CNS-depressant or orthostatic effects (e.g., sedating antihistamines, psychotropic drugs like tricyclic antidepressants, phenothiazines, and neuroleptics), patients should be made aware of the possibility of additive effects with methadone and counseled to avoid activities requiring mental alertness until they know how these agents affect them.

References
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