2,5-Dimethoxy-4-chloroamphetamine (DOC) is a psychedelic drug of the phenethylamine, amphetamine, and DOx families. It was presumably first synthesized by Alexander Shulgin, and was described in his book PiHKAL (Phenethylamines i Have Known And Loved).

Recreational availability and use of DOC are rare. The drug is expected to become a controlled substance in the United States in the near future as of 2025.

A normal average dose of DOC ranges from 0.2–7.0 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.

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.

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.

DOC acts as a serotonin 5-HT_2A and 5-HT_2C receptor agonist. Its psychedelic effects are mediated via its actions on the 5-HT_2A receptor.^{[citation needed]}

The drug is inactive as a monoamine releasing agent and reuptake inhibitor.

DOC produces the head-twitch response, a behavioral proxy of psychedelic-like effects, in rodents.