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MT-45, a new psychoactive substance associated with hearing loss and unconsciousness
A Helander1, M Bäckberg, O Beck
1Department of Laboratory Medicine, Karolinska Institutet , Stockholm , Sweden.
Background:
MT-45 (1-cyclohexyl-4-(1,2-diphenylethyl)piperazine) is an opioid analgesic drug candidate developed in the 1970s that has recently been introduced as a new psychoactive substance (NPS) on the "recreational" drug market. We describe a case series of non-fatal intoxications associated with MT-45 within the Swedish STRIDA project.
Study Design:
Observational case series of consecutive patients with admitted or suspected intake of NPS presenting to hospitals in Sweden from November 2013 to February 2014.
Patients And Methods:
Blood and urine samples were collected from intoxicated patients presenting to emergency departments and intensive care units over the country. NPS analysis was performed by an LC-MS/MS multi-component method. Clinical data were collected when caregivers consulted the Poisons Information Centre and also retrieved from medical records. CASE SERIES. Among nine intoxications where MT-45 was detected in the biological samples, four cases were indicated to only involve MT-45, while one or several psychoactive substances were found along with MT-45 in the others. All patients were men aged 17-32 years and they commonly presented with opioid-like adverse symptoms, such as unconsciousness and respiratory depression. Naloxone appeared to have utility in the treatment of MT-45 intoxication in several cases. Three patients complained of bilateral hearing loss that in one case persisted after two weeks.
Conclusion:
MT-45 should be added to the growing list of harmful NPS causing life-threatening poisonings, and rapid actions taken to make it a controlled substance.
Insights
MT-45, a new psychoactive substance, caused non-fatal intoxications including unconsciousness and respiratory depression. Naloxone showed utility in treatment, but hearing loss was a persistent side effect in some cases.
Area of Science:
- Toxicology
- Pharmacology
- Emergency Medicine
Background:
- MT-45 (1-cyclohexyl-4-(1,2-diphenylethyl)piperazine) is an opioid analgesic candidate from the 1970s now appearing as a new psychoactive substance (NPS) on the recreational drug market.
- This study details a series of non-fatal intoxications linked to MT-45 exposure within Sweden.
Purpose of the Study:
- To report on the clinical characteristics and outcomes of patients experiencing MT-45 intoxication.
- To assess the potential utility of naloxone in managing MT-45 overdose.
- To highlight the emerging public health threat posed by MT-45.
Main Methods:
- An observational case series was conducted involving patients presenting with suspected NPS intake in Sweden between November 2013 and February 2014.
- Biological samples (blood, urine) were analyzed for NPS using LC-MS/MS.
- Clinical data were gathered from the Poisons Information Centre and medical records.
Main Results:
- MT-45 was detected in nine intoxication cases; four involved MT-45 exclusively, while five involved co-ingestion with other psychoactive substances.
- All affected patients were males aged 17-32 years, presenting with opioid-like symptoms including unconsciousness and respiratory depression.
- Naloxone was beneficial in treating MT-45 intoxication. Three patients reported bilateral hearing loss, persisting in one case for over two weeks.
Conclusions:
- MT-45 is a harmful NPS causing severe, life-threatening poisonings.
- Urgent action is recommended to classify MT-45 as a controlled substance to mitigate public health risks.
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