2,5-Dimethoxy-4-iodoamphetamine

DOI
Clinical data
Other names	DOI; 2,5-Dimethoxy-4-iodoamphetamine; 4-Iodo-2,5-dimethoxyamphetamine
Routes of; administration	Oral
Drug class	Serotonergic psychedelic; Hallucinogen; Serotonin 5-HT2 receptor agonist; Anti-inflammatory agent
ATC code	None;
Legal status
Legal status	BR: Class F2 (Prohibited psychotropics); CA: Schedule I;
Pharmacokinetic data
Duration of action	16–30 hours
Identifiers
	IUPAC name 1-(4-iodo-2,5-dimethoxyphenyl)propan-2-amine;
CAS Number	64584-34-5 [correct] ; 82864-06-0 ((R)-DOI); 99665-04-0 ((S)-DOI); 42203-78-1 (HCl);
PubChem CID	1229;
IUPHAR/BPS	147;
ChemSpider	1192 ;
UNII	Q2E57V2WS3;
ChEMBL	ChEMBL6616 ;
CompTox Dashboard (EPA)	DTXSID7040520 ;
Chemical and physical data
Formula	C11H16INO2
Molar mass	321.158 g·mol−1
3D model (JSmol)	Interactive image;
Melting point	201.5 °C (394.7 °F) (hydrochloride)
Solubility in water	10 mg/mL
	SMILES IC(C=C1OC)=C(OC)C=C1CC(C)N;
	InChI InChI=1S/C11H16INO2/c1-7(13)4-8-5-11(15-3)9(12)6-10(8)14-2/h5-7H,4,13H2,1-3H3 ; Key:BGMZUEKZENQUJY-UHFFFAOYSA-N ;
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2,5-Dimethoxy-4-iodoamphetamine (DOI) is a psychedelic drug of the phenethylamine, amphetamine, and DOx families. It is little-used recreationally, but is widely used in scientific research in the study of psychedelics and serotonin receptors. The drug is taken orally.

It acts as a potent serotonin 5-HT₂ receptor agonist, including of the serotonin 5-HT_2A and 5-HT_2C receptors. Analogues of DOI include 2C-I, DOB, DOC, DOM, and 25I-NBOMe, among others.

DOI was first described in the scientific literature by Ronald Coutts and Jerry Malicky in 1973. Subsequently, it was described in greater detail by Alexander Shulgin in his 1991 book PiHKAL (Phenethylamines I Have Known and Loved). DOI has been encountered as a novel designer drug. Owing to their very long and disagreeable durations however, DOI and other DOx drugs have seen very little recreational availability and use. Unlike many other psychedelic drugs, DOI is not an explicitly controlled substance in the United States. However, in 2023, the Drug Enforcement Administration (DEA) began taking steps to make DOI a controlled substance. As of late 2025, DOI is poised to become a Schedule I controlled substance in the United States.