Hallucinogens, also called psychedelics, have been used for over a millennium. The best known are LSD, psilocybin, mescaline, and PCP. These substances can induce hallucinations and cause somatic and psychological symptoms. Since the Controlled Substances Act of 1970, research on their long-term consequences or potential benefits has been very limited. These drugs are typically misused rather than abused. Recently, renewed interest has emerged, which may lead to possible therapeutic options.
Psychedelic-assisted therapy effectively treats the multidimensional psychological distress common at the end of life, which includes psychosocial, existential, and physical symptom burdens. Ketamine and cannabis may provide rapid relief for symptom burden. More data is needed, especially in elderly populations.