DOB
1-(4-bromo-2,5-dimethoxyphenyl)propan-2-amine
Overview
DOB belongs to Psychedelics / Phenethylamines.
Effects
Subjective effects vary. What a substance feels like depends on dose, individual physiology,
mindset, and setting. The points below describe commonly reported effects, not guaranteed, uniform, or
desirable outcomes.
- Intensely stimulating and long-lasting, with pronounced wakefulness and a heavy body load (pins-and-needles, muscle tension and tremor)
- Strong, sharp, 'synthetic' visual geometry and, in darkness, high-level internal hallucinations
- Marked mental stimulation that can tip into anxiety or paranoia, especially given the very long duration
Dosing & duration
Harm-reduction note: These are commonly cited reference ranges, not a recommendation or a
“safe” dose. Potency, purity, body chemistry, tolerance, and drug combinations vary widely. Start
low, go slow, wait for full effects before redosing, and never assume an unknown product matches these
figures. Missing data is not evidence of safety.
Oral. DOB is extremely potent and very long-acting, so precise low dosing (ideally volumetric from a solution) is essential. Common oral doses are only ~1–3 mg for racemic DOB (about 1–2 mg for the more active (R)-DOB). Effects come up slowly (often 1–3 hours), which has repeatedly led people to redose and overdose: do not redose. Expect an exceptionally long experience.
Dose ranges
Threshold
~0.2 mg
Light
0.2–0.75 mg
Common
0.75–1.75 mg
Strong
1.75–3 mg
Duration
onset
30–90 min
peak
6–10 h
total
14–24 h (can extend to ~30 h)
Chemical & Physical Properties
| Formula | C11H16BrNO2 |
| Molar mass | 274.15 g/mol |
| State | Solid (usually the water-soluble hydrochloride or hydrobromide salt) |
| Melting point | 63–65 °C (free base), 207–208 °C (hydrochloride salt) |
| Boiling point | unavailable: true. reason: a crystalline solid that decomposes on strong heating rather than boiling. No reliable experimental boiling point is reported |
| Density | unavailable: true. reason: no reliable experimental value is reported for the solid |
| Vapor pressure | Not reported |
| pKa | Not reported |
| LogP | 2.58 (experimental, PubChem/HSDB) |
| Solubility | Not reported |
| Refractive index | Not reported |
Identifiers & Synonyms
| CAS | 64638-07-9 |
| CAS (enantiomer) | |
| PubChem CID | 62065 |
| InChIKey | FXMWUTGUCAKGQL-UHFFFAOYSA-N |
| InChI | InChI=1S/C11H16BrNO2/c1-7(13)4-8-5-11(15-3)9(12)6-10(8)14-2/h5-7H,4,13H2,1-3H3 |
| SMILES | CC(CC1=CC(=C(C=C1OC)Br)OC)N |
Synonyms
- 4-Bromo-2,5-dimethoxyamphetamine
- Bromo-DMA
- Brolamfetamine (INN)
- DOB
Pharmacodynamics & Biochemistry
A potent, exceptionally long-acting psychedelic phenethylamine: the α-methyl (amphetamine) homologue of 2C-B. Its effects come from potent agonism at the 5-HT2A receptor (sub-nanomolar to low-nanomolar affinity), with additional agonism at 5-HT2C and 5-HT2B. It is far more potent and much longer-acting than 2C-B. (R)-DOB is the more active enantiomer (eutomer). The amphetamine side chain resists monoamine-oxidase breakdown, contributing to its very long duration of action. Agonism at 5-HT2B and at vascular 5-HT2A receptors underlies a pronounced vasoconstrictor effect that can become dangerous in overdose (ergotism-like arterial spasm).
Biological targets
- 5-HT2A
- 5-HT2C
Binding & functional measurements
| Target | Measurement | Species |
|---|---|---|
| 5-HT2A receptor | Ki 0.60 ± 0.10 nM | Human |
| 5-HT2C receptor | Ki 1.3 ± 0.20 nM | Human |
| 5-HT2B receptor | Ki 27 ± 4.6 nM | Human |
| 5-HT7 receptor | Ki 506 nM | Human |
| 5-HT1E receptor | Ki 556 nM | Human |
| α2C-adrenoceptor | Ki 594 nM | Human |
| 5-HT1D receptor | Ki 636 nM | Human |
| D3 receptor | Ki 808 nM | Human |
| 5-HT1B receptor | Ki 941 nM | Human |
| α2B-adrenoceptor | Ki 1,527 nM | Human |
| I1 imidazoline receptor | Ki 1,596 nM | Human |
| σ1 receptor | Ki 2,193 nM | Human |
| 5-HT1A receptor | Ki 2,550 nM | Human |
| α2A-adrenoceptor | Ki 4,266 nM | Human |
| 5-HT5A receptor | Ki 5,311 nM | Human |
| 5-HT6 receptor | Ki 5,535 nM | Human |
| Serotonin transporter | Ki 8,538 nM | Human |
| H1 receptor | Ki 9,120 nM | Human |
| 5-HT2A receptor | EC50 1.5 nM Emax 74% | Human |
| 5-HT2B receptor | EC50 2.9 nM Emax 69% | Human |
| 5-HT2C receptor | EC50 7.8 nM Emax 65% | Human |
Pharmacokinetics
| Bioavailability | Not reported |
| Tmax | Not reported |
| Half-life | Not established in humans, but effects are exceptionally long (≈18–30 h) |
| Vd | Not reported |
| Protein binding | Not reported |
| Metabolism | Hepatic. The α-methyl (amphetamine) group resists monoamine oxidase, contributing to a very long duration of action. Detailed human metabolic pathways are not well characterised |
| Excretion | Not reported |
Toxicology & Safety
Harm-reduction note: Toxicity and risk depend on dose, route, purity, combinations, setting, and individual
health factors. Missing harms should never be interpreted as evidence of safety.
Not reported
DOB is extraordinarily potent, active at only about 1–3 mg, so it is very easy to overdose, and it has sometimes been mis-sold as LSD on blotter despite needing a far larger amount than fits on a typical tab. Its most dangerous feature is pronounced vasoconstriction: at high doses it can cause diffuse arterial spasm and ergotism-like limb ischaemia. Reported overdoses include convulsions, a fatality at ~35 mg, and a case where ~75 mg led to gangrene requiring amputation. Severe vasospasm has been treated with vasodilators. Effects are also exceptionally long and unpredictable (often 18–30 hours), which makes redosing especially dangerous, never redose because it 'hasn't come up yet'. Accurate milligram (ideally volumetric) dosing is essential. Limited data must never be read as evidence of safety.[5][1]
Legal Status
Legal note: Legal status can change over time and may vary by country, region, formulation, analogue status,
prescription context, and enforcement practice. Always confirm with current official sources before relying on this section.
US: Schedule I. UK: Class A. DE: BtMG Anlage I
Interactions & Contraindications
Drug interactions
Stimulants (amphetamines, cocaine), Vasoconstrictors Dangerously compound DOB's already strong vasoconstriction and cardiovascular strain, a particular risk given its long duration.
Lithium, Tramadol Raise the risk of seizures and psychosis with psychedelics.
SSRIs, SNRIs, MAOIs Add to serotonergic load. MAOIs may unpredictably intensify and prolong effects.
Cannabis Can intensify effects and increase anxiety or panic.
Contraindications
Cardiovascular disease, hypertension or arrhythmia includes Raynaud's or other vascular conditions, DOB is a strong vasoconstrictor.
Personal or family history of psychosis, schizophrenia or bipolar disorder
Concurrent MAOI, SSRI/SNRI or other serotonergic medication includes MAO inhibitors, and avoid concurrent vasoconstrictors or stimulants.
Settings where impairment or dissociation risks injury (driving, water, heights) extreme potency and 18-30 h duration.
No interactions or contraindications listed.
Usage & Context
- Research.
- Recreational.
Sources & Evidence
- Shulgin A, Shulgin A (1991). PiHKAL: A Chemical Love Story — entry #62 (DOB)
- Shulgin AT, Sargent T, Naranjo C (1971). 4-Bromo-2,5-dimethoxyphenylisopropylamine, a new centrally active amphetamine analog. Pharmacology 5:103-7.
PMID 5570923 · doi:10.1159/000136181
- Nichols DE (2016). Psychedelics. Pharmacol Rev 68:264-355.
PMID 26841800 · doi:10.1124/pr.115.011478
- PsychonautWiki: DOB (dosage, duration & effects) CC BY-SA 4.0
- Wikipedia: DOB (psychedelic) CC BY-SA 4.0
- Wikipedia chembox (melting points). PubChem CID 62065 (LogP) CC BY-SA 4.0