2,5-Dimethoxy-4-chloroamphetamine (DOC) is a psychedelic drug of the phenethylamine and amphetamine chemical classes. It was presumably first synthesized by Alexander Shulgin, and was described in his book PiHKAL (Phenethylamines i Have Known And Loved). Chemistry DOC is a substituted alpha-methylated phenethylamine, a class of compounds commonly known as amphetamines. The phenethylamine equivalent (lacking the alpha-methyl group) is 2C-C. DOC has a stereocenter and (R)-(−)-DOC is the more active stereoisomer. Pharmacology DOC acts as a selective 5-HT2A, 5-HT2B, and 5-HT2C receptor partial agonist. Its psychedelic effects are mediated via its actions on the 5-HT2A receptor. Dosage A normal average dose of DOC ranges from 0.5–7.0 mg the former producing threshold effects, and the latter producing extremely strong effects. Onset of the drug is 1–3 hours, peak and plateau at 4–8 hours, and a gradual come down with residual stimulation at 9-20h. After effects can last well into the next day. Effects Unlike simple amphetamines, DOC is considered a chemical that influences cognitive and perception processes of the brain. The strongest supposed effects include open and closed eye visuals, increased awareness of sound and movement, and euphoria. In the autobiography PiHKAL, Alexander Shulgin included a description of DOC as "an archetypal psychedelic" (#64); its presumed full-range visual, audio, physical, and mental effects show exhilarating clarity, and some overwhelming, humbling, and "composting"/interweaving effects. Dangers Very little data exists about the toxicity of DOC. In April 2013, a case of death due to DOC was reported. The source does not specify whether the drug alone caused the death. In 2014, a death was reported in which DOC was directly implicated as the sole causative agent in the death of a user. The autopsy indicated pulmonary edema and a subgaleal hemorrhage. Detection in biological specimens DOC may be quantitated in blood, plasma or urine by gas chromatography-mass spectrometry or liquid chromatography-mass spectrometry to confirm a diagnosis of poisoning in hospitalized patients or to provide evidence in a medicolegal death investigation. Blood or plasma DOC concentrations are expected to be in a range of 1–10 μg/L in persons using the drug recreationally, >20 μg/L in intoxicated patients and >100 μg/L in victims of acute overdosage. Popularity Although rare on the black market, it has been available in bulk and shipped worldwide by select elite "Grey Market" Research Chemical suppliers for several years. Sales of DOC on blotting paper and in capsules was reported in late 2005