{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"medRxiv"}],"indexed":{"date-parts":[[2026,5,20]],"date-time":"2026-05-20T08:12:16Z","timestamp":1779264736143,"version":"3.51.4"},"posted":{"date-parts":[[2025,5,11]]},"group-title":"Addiction Medicine","reference-count":13,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2025,5,11]],"date-time":"2025-05-11T00:00:00Z","timestamp":1746921600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,5,17]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:sec>\n                  <jats:title>Introduction<\/jats:title>\n                  <jats:p>The purity, accessibility, and affordability of illicit methamphetamine has increased in recent decades, which has been linked to rising rates of methamphetamine-involved overdoses, psychosis, cardiovascular events, and other health consequences. Nevertheless, information about the quantity of methamphetamine used by regular consumers has been limited, despite the potential clinical utility of exposure quantification.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>From August 2024-April 2026, self-reported daily methamphetamine consumption was assessed among n=94 individuals in Los Angeles County. Methamphetamine samples (n=256) were analyzed for purity using liquid chromatography-mass spectrometry. Bioavailability by route of administration and stimulant equivalency were obtained from literature. A simulation model leveraging bootstrapping with 1,000,000 draws was used to estimate oral amphetamine milligram equivalents (AME).<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>The average reported methamphetamine consumption was 1.09g daily (95% prediction interval: 0.07-4.00). Average purity was 84.52% (95% PI: 14.90%-100.00%). Given estimated average bioavailability of 66.41% (95% PI: 39.35%-85.24%), the average consumer used an estimated 1,432.54 AME daily (95% PI: 35.74-6,973.05).<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Discussion<\/jats:title>\n                  <jats:p>We estimate that consumers of methamphetamine in Los Angeles use an average daily stimulant dose (nearly 1,500 oral AME) about 25-fold higher than the maximum typical recommended clinical dose of mixed amphetamine salts (60mg). This may help explain the limited efficacy of prescription stimulant treatment for methamphetamine use disorder, which typically employs considerably lower quantities. Given this high dose, these findings shed light on the rising incidence of methamphetamine-related sequelae, such as psychosis, cardiovascular complications, and sudden death. Although exposure quantification is commonplace for alcohol and tobacco use disorders, uncertainties in illicit drug markets has complicated this practice for most illicit drugs. This study supports leveraging emerging information from drug checking programs so that clinicians can approximate exposure quantification.<\/jats:p>\n                <\/jats:sec>","DOI":"10.1101\/2025.05.09.25327334","type":"posted-content","created":{"date-parts":[[2025,5,11]],"date-time":"2025-05-11T13:10:21Z","timestamp":1746969021000},"source":"Crossref","is-referenced-by-count":0,"title":["What Dose of Methamphetamine Do Regular Consumers Use Daily? Estimating Oral Amphetamine Milligram Equivalents"],"prefix":"10.64898","author":[{"given":"Joseph R.","family":"Friedman","sequence":"first","affiliation":[{"name":"Department of Psychiatry, University of California, San Diego"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Adam J.","family":"Koncsol","sequence":"additional","affiliation":[{"name":"Department of General Internal Medicine and Health Services Research, University of California, Los Angeles"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Caitlin A.","family":"Molina","sequence":"additional","affiliation":[{"name":"Department of General Internal Medicine and Health Services Research, University of California, Los Angeles"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruby","family":"Romero","sequence":"additional","affiliation":[{"name":"Department of General Internal Medicine and Health Services Research, University of California, Los Angeles"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jasmine","family":"Feng","sequence":"additional","affiliation":[{"name":"Department of General Internal Medicine and Health Services Research, University of California, Los Angeles"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michelle","family":"Poimboeuf","sequence":"additional","affiliation":[{"name":"Department of General Internal Medicine and Health Services Research, University of California, Los Angeles"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Morgan E.","family":"Godvin","sequence":"additional","affiliation":[{"name":"Department of General Internal Medicine and Health Services Research, University of California, Los Angeles"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Siddarth","family":"Puri","sequence":"additional","affiliation":[{"name":"Medical Director, County of San Luis Obispo, California"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carla","family":"Marienfeld","sequence":"additional","affiliation":[{"name":"Department of Psychiatry, University of California, San Diego"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chelsea L.","family":"Shover","sequence":"additional","affiliation":[{"name":"Department of General Internal Medicine and Health Services Research, University of California, Los Angeles"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"54368","reference":[{"key":"2026052000450613000_2025.05.09.25327334v3.1","doi-asserted-by":"publisher","DOI":"10.1001\/jamapsychiatry.2021.2588"},{"key":"2026052000450613000_2025.05.09.25327334v3.2","doi-asserted-by":"publisher","DOI":"10.1176\/appi.ajp.22010076"},{"key":"2026052000450613000_2025.05.09.25327334v3.3","doi-asserted-by":"publisher","DOI":"10.1016\/j.drugalcdep.2024.111409"},{"key":"2026052000450613000_2025.05.09.25327334v3.4","doi-asserted-by":"publisher","DOI":"10.1111\/add.16318"},{"key":"2026052000450613000_2025.05.09.25327334v3.5","doi-asserted-by":"publisher","DOI":"10.1101\/2025.03.18.25323868"},{"key":"2026052000450613000_2025.05.09.25327334v3.6","unstructured":"Prescription psychostimulants for the treatment of stimulant use disorder: a systematic review and meta-analysis | Psychopharmacology. Accessed April 26, 2025. https:\/\/link.springer.com\/article\/10.1007\/s00213-020-05563-3"},{"key":"2026052000450613000_2025.05.09.25327334v3.7","doi-asserted-by":"publisher","DOI":"10.1038\/clpt.2010.307"},{"key":"2026052000450613000_2025.05.09.25327334v3.8","doi-asserted-by":"publisher","DOI":"10.1111\/j.1360-0443.2009.02717.x"},{"key":"2026052000450613000_2025.05.09.25327334v3.9","doi-asserted-by":"publisher","DOI":"10.1176\/appi.ajp.20230329"},{"key":"2026052000450613000_2025.05.09.25327334v3.10","doi-asserted-by":"publisher","DOI":"10.1111\/add.16409"},{"key":"2026052000450613000_2025.05.09.25327334v3.11","doi-asserted-by":"publisher","DOI":"10.15585\/mmwr.mm7306a2"},{"key":"2026052000450613000_2025.05.09.25327334v3.12","doi-asserted-by":"publisher","DOI":"10.1016\/j.drugalcdep.2024.111318"},{"key":"2026052000450613000_2025.05.09.25327334v3.13","unstructured":"Burchim S. Methamphetamine Use, Mental Health Comorbidities, and Treatment in Rural and Urban Areas, 2016-2019. UW Department of Family Medicine, Rural Health Research Center; 2026."}],"container-title":[],"original-title":[],"link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1101\/2025.05.09.25327334","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,20]],"date-time":"2026-05-20T07:45:15Z","timestamp":1779263115000},"score":1,"resource":{"primary":{"URL":"http:\/\/medrxiv.org\/lookup\/doi\/10.1101\/2025.05.09.25327334"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,5,11]]},"references-count":13,"URL":"https:\/\/doi.org\/10.1101\/2025.05.09.25327334","relation":{},"subject":[],"published":{"date-parts":[[2025,5,11]]},"subtype":"preprint"}}