Tolerance hallucinogens

DSM-IV-TR (American Psychiatric Association 2000) criteria for hallucinogen intoxication are presented in Table 6-3. The normally used quantity of LSD ingested ranges from 30 to 400 pg, but doses as low as 20 pg may cause clinically detectable symptoms (Strassman 1984). However, tolerance to the effect of LSD develops relatively quickly, so that chronic users increase their dose over time. 

N,N-DMT DMT (N,N-dimethyltryptamine) is one of the most hallucinogenic compounds known. DMT is not active orally (unless in the form of an ayahuasca brew), but must be smoked in it s freebase form to experience its effects. (DMT can be taken orally when mixed with a MAOIs, but this is not recommended for the first time user.) The body quickly builds a tolerance for the drug. Your DMT dose must be taken within 60 seconds. Any more of the drug after this first minute will not enhance the experience. It is recommended to give at least one hour before attempting another DMT trip. 

Mg/kg LSD is given at 3 hourly intervals with the animals being tested only after the last injection (32). Cross tolerance has been observed to other indole and phenylalkylamine hallucinogens (11). Similar effects were also reported for other hallucinogens (10) with an order of potency that paralleled that seen in humans (2) that is, the (hallucinogenic) -isomer of LSD was about 10 times as potent as psilocybin and 100 times as potent as mescaline (10). 

Psilocybin and psilocin are believed to work through mechanisms similar to LSD and other indole hallucinogens. Similar to LSD, chronic psilocybin in take also down-regulates 5-HT2 receptors, which parallels the development of behavioral tolerance (Buckholtz et al. 1990). 

Similar to LSD and other monoamine hallucinogens, mescaline suppresses locomotor and exploratory behavior in novel environments (Wing et al. 1990). Also similar to LSD, tolerance develops to the behavioral effects of chronic doses of mescaline (Murray et al. 1977). Mescaline increases aggression in rat models (Sbordone et al. 1978) however, this is an elicited aggression (by electric shock) and does not necessarily generalize to human behavior. Increased aggression is not characteristic of humans using mescaline. 

Unlike most hallucinogens, tolerance to subjective effects is not observed with DMT, even over several closely spaced doses (Strassman 1996). In contrast, tolerance was evident to hormonal and heart-rate responses. 

LSD is very potent and produces both CNS and peripheral effects. Because of the rapid tolerance produced with these drugs, the typical abuser does not use the drug on a daily basis. Generally, an hallucinogen is abused approximately once per month. 

Hallucinogenic drugs like LSD are not reinforcing In animals, In that they will not self-admlnister these drugs. SNA, however, Is self-administered In large quantities by monkeys equipped with intravenous catheters when access is unlimited. Tolerance of the acute... 

These CNS stimulants have sometimes been referred to as hallucinogens but are more appropriately referred to as psychomimetics because few, if any, cause an absence of reality, that is, a hallucination. Psychomimetics distort or heighten sensory input, produce dream-like states, and can be psychologically addictive. There is no consistent evidence that they can produce tolerance or physical dependence. This is not to imply that these drugs are innocuous. The distortions of reality can lead to panic, anxiety, lack of concentration, and psychotic states to say the least. 

Use of these hallucinogens has not been associated with dependence or physiologic withdrawal symptoms. This is probably because tolerance develops rapidly, so that closely spaced dosing would be necessary to cause dependence such frequent dosing is unusual. 

Cross-tolerance occurs between LSD, mescaline and psilocybin, but not between this group and the amphetamine type of hallucinogens. This... 

Flashbacks, or reoccurrence of hallucinogenic effects, have been reported. Persistent psychosis, anxiety, and depression have been described following mescaline use. Tolerance, but not physical dependence, to mescaline s effects has been reported in humans. Additionally, chronic users may demonstrate crosstolerance to the effects of LSD or psilocybin. 

Unfortunately, nalorphine has hallucinogenic side-effects resulting from the activation of a non-analgesic receptor, and is therefore unsuitable as an analgesic, but for the first time a certain amount of analgesia had been obtained without the side-effects of respiratory depression and tolerance. 

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