Mirtazapine, an existing antidepressant medication, has shown promise in treating methamphetamine use disorder in a new Phase 3 clinical trial, addressing a significant treatment gap. The 2026 McKetin trial found that mirtazapine 30 mg daily reduced methamphetamine use by approximately two additional days per 28-day period compared with placebo, without safety concerns.
Approximately 2.4 million Americans used methamphetamine in the past 12 months according to the 2024 National Survey on Drug Use and Health. Currently, there are no FDA-approved medications for methamphetamine use disorder treatment, leaving the field with what researchers call “therapeutic scarcity.” The trial enrolled approximately 344 participants randomized to mirtazapine or placebo for 12 weeks. The primary outcome—reduction in days of methamphetamine use—was statistically significant, favoring mirtazapine.
Mirtazapine’s value lies in its availability, familiarity to clinicians, and low cost. It requires no induction protocol and can be prescribed in primary care, outpatient, or residential treatment settings. The medication counters physiologic disruptions characteristic of chronic stimulant use by helping with sleep deprivation, hyperarousal, and dysphoria—all common in methamphetamine use disorder.
Polysubstance use dominates methamphetamine use disorder treatment, with approximately 90% of meth users reporting concurrent use of opioids, alcohol, cannabis, nicotine, and other drugs, averaging 3.3 substances. In psychostimulant overdose deaths, approximately 50% also involve opioids. Meth plus opioid co-use increases injection drug use by 132%, approximately doubles infectious disease risk, and triples criminal justice involvement compared to single-drug use.
Recent evidence supports a layered treatment model combining mirtazapine for mood and physiologic dysregulation with naltrexone-bupropion targeting reward-driven stimulant use.
This article is an AI-assisted summary. All facts and figures are drawn from the original report: https://headtopics.com/news/mirtazapine-an-existing-antidepressant-fills-a-82903764