{"brand":"Compound Laws","url":"https://compoundlaws.com/compounds/endomorphin-1/colorado/","compound":{"slug":"endomorphin_1","name":"Endomorphin-1","same_as":"https://en.wikipedia.org/wiki/Endomorphin"},"jurisdiction":{"code":"CO","name":"Colorado"},"as_of":"2026-07-18","answer":"As of July 18, 2026, Endomorphin-1 is legal to sell at retail in Colorado. Unscheduled - legal as research-use-only; no operative instrument reaches a structurally-dissimilar opioid peptide. Controlling source: C.R.S. 18-18-102(5) (controlled substance analog).","forms":[{"form":"all","label":"All forms","status":"legal","state_status":null,"federal_overlay":false,"headline":"Unscheduled - legal as research-use-only; no operative instrument reaches a structurally-dissimilar opioid peptide","rule_type":"permanent","tier":"unscheduled","schedule_class":null,"limit":null,"effective_date":null,"verified_at":"2026-07-18","confidence":"confirmed","verbatim_excerpt":"C.R.S. 18-18-102(6)(a): \"'Controlled substance analog' means a substance the chemical structure of which is substantially similar to the chemical structure of a controlled substance in or added to schedule I or II AND: (I) Which has a stimulant, depressant, or hallucinogenic effect on the central nervous system substantially similar ...; or (II) ... which the individual represents or intends to have [such effect] ...\" (6)(b) excludes approved/investigational substances and those not intended for human consumption. [Conjunctive - structure prong fails for a peptide.]","excerpt_source_url":"https://content.leg.colorado.gov/sites/default/files/images/olls/crs2024-title-18.pdf","citations":[{"title":"C.R.S. 18-18-102(5) (controlled substance analog)","url":"https://codes.findlaw.com/co/title-18-criminal-code/co-rev-st-sect-18-18-102/","pinpoint":null,"publisher":"Code mirror","type":"statute","primary":true,"official":true},{"title":"C.R.S. 18-18-102 (opiate def)","url":"https://codes.findlaw.com/co/title-18-criminal-code/co-rev-st-sect-18-18-102/","pinpoint":null,"publisher":"Code mirror","type":"statute","primary":false,"official":true}],"history":[]}],"neighbors":[{"code":"AZ","status":"legal"},{"code":"KS","status":"legal"},{"code":"NE","status":"legal"},{"code":"NM","status":"legal"},{"code":"OK","status":"legal"},{"code":"UT","status":"legal"},{"code":"WY","status":"legal"}],"laws":[{"citation":"C.R.S. § 18-18-203(2)(c) (Schedule I hallucinogens — does NOT name it); analog reach via C.R.S. § 18-18-203(2)(g) + § 18-18-102(6).","title":null,"official_url":"https://colorado.public.law/statutes/crs_18-18-203","source_label":"MIRROR","effective_date":null,"retrieved_date":"2026-06-19","text_hash":"964bba3a8434c09dd9e031c4f18211b1c18ac8a6df7ec331c39136793c8f8287"},{"citation":"C.R.S. 18-18-203 (Schedule I), (2)(c) hallucinogenic substances; Colorado Revised Statutes 2024 official PDF","title":"C.R.S. 18-18-203 (Schedule I), (2)(c) hallucinogenic substances; Colorado Revised Statutes 2024 official PDF","official_url":"https://leg.colorado.gov/sites/default/files/images/olls/crs2024-title-18.pdf","source_label":"OFFICIAL","effective_date":null,"retrieved_date":"2026-10-08","text_hash":"48a73c7b97b388de63a3b1a7281095cc872b35d3bc5b9f2072e7e839b23c6842"},{"citation":"C.R.S. Sec. 18-18-203(2)(g)","title":"Schedule I - in-schedule controlled substance analog","official_url":"https://leg.colorado.gov/sites/default/files/images/olls/crs2024-title-18.pdf","source_label":"MIRROR","effective_date":null,"retrieved_date":"2026-07-20","text_hash":"145428adb15e2af08f928363e5326737bdba8f11dea25dae133de72624dda6b3"}]}