Psychotomimetic effects

Delta Dysphoria, psychotomimetic effects (eg, hallucinations), respiratory and vasomotor stimulations caused by drugs with antagonist activity... 

Although the exact mechanisms of action of LSD and tryptamine-related compounds are incompletely understood (Freedman 1987), there is convincing evidence relating the psychotomimetic effects of these substances to serotonergic transmission in the brain (Davis 1987 Freedman 1987 McCall 1986 Nichols 2004). An antagonism of 5-HT in the rat brain is sufficient to cause a fourfold decrease in the threshold dose ofLSD (Appel and Freedman 1964). 

Phencyclidine (1 -[1-phenylcyclohexyl]pi peridine HC1 PCP) and its active derivatives produce unique behavioral effects in animals and psychotomimetic effects in humans. Drugs of this class have been demonstrated to bind saturably, reversibly, and with high affinity to specific binding sites in brain (Hampton et al. 1982 Quirion et al. 1981 Sircar and Zukin 1983 Vincent et al. 1979 Zukin and Zukin 1979). These sites have been shown to exhibit a characteristic heterogeneous regional distribution pattern (Quirion et al. 1981 Sircar et al., submitted for publication Zukin and Zukin 1979) distinct from that of any other receptor type. 

What is the action of PCC (a PCP analog without psychotomimetic effects) on the numerous synapses that PCP affects ... 

Emotional effects Morphine creates a pleasant, euphoric state, which is an aspect of the behaviorally reinforcing effect. The subjective state produced by opioids is often described as ecstatic and is compared to a sexual experience. These effects are most likely mediated by iJ and possibly 5 receptors, and interactions with the mesolimbic dopamine system (Shippenberg et al. 1993 Di Chiara and North 1992 Wise 1989). In contrast, x opioids have dysphoric and psychotomimetic effects (Kumor et al. 1986). 

Although this drug is categorized as a local anesthetic, I have chosen to put it in with the hallucinogens because of the psychotomimetic effects that it produces. Cocaine is not a phenylethyl-amine, but it produces central nervous system arousal or stimulant effects which closely resemble those of the amphetamines, the methylenedioxyamphetamines in particular. This is due to the inhibition by cocaine of re-uptake of the norepinephrine released by the adrenergic nerve terminals, leading to an enhanced adrenergic stimulation of norepinephrine receptors. The increased... 

Pharmacology Nalmefene, an opioid antagonist, is a 6-methylene analog of naltrexone. Nalmefene prevents or reverses the effects of opioids, including respiratory depression, sedation, and hypotension. Nalmefene has no opioid agonist activity it does not produce respiratory depression, psychotomimetic effects or pupillary constriction, and no pharmacological activity was observed when it was administered in the absence of opioid agonists. Nalmefene can produce acute withdrawal symptoms in individuals who are opioid-dependent. 

Type B effects vary depending on the drug used, e.g. heparin and thrombocytopenia, ticlopidine and thrombocytopenia. Clopidrogel shows excellent acceptability. According to the results of phase I and phase II trials, the neurocytoprotectors currently under development have a very variable safety profile. Anti-NMDA agents can induce psychostimulation, psychotomimetic effects and increase blood pressure. For cardiac effects, QTc lengthening is still a problem with eliprodil and lubeluzole. 

Antagonists such as D-(-)-2-amino-5-phosphono-valeric acid (D-AP V), which competitively block NMDA receptors, cause numerous side-effects such as memory impairment, psychotomimetic effects, ataxia and motor dis-coordi-nation, since they also impair normal synaptic transmission. The challenge has therefore been to develop NMDA receptor antagonists that prevent the pathological activation of NMDA receptors but allow their physiological activation. 

The most common side effect of pentazocine is sedation resulting from an interaction with the K-receptor. Also observed are sweating, dizziness, psychotomimetic effects, anxiety, nightmares, and headache. Nausea and vomiting are less frequent than with morphine. Respiratory depression and increased heart rate, body temperature, and blood pressure accompany overdose. Naloxone is effective in reducing the respiratory depression but requires the use of higher doses than for morphine overdose. 

MDA, which is similar to MDMA, has been termed the love drug because it produces a feeling of closeness to others. Typically, a dose of 75 mg produces the primary psychotomimetic effects, while a dose of 150 mg produces LSD-like effects, and a dose of 300 mg produces amphetaminelike CNS stimulation. The amphetaminelike stimulation of the CNS and periphery is prominent with both MDA and MDMA. To a lesser degree this stimulation also occurs with LSD. The effects that can be produced by stimulatory doses of hallucinogens include tachycardia, hypertension, and arrhythmias. 

Russo, E. B., A. Merzouki, J. M. Mesa, K. A. Frey, and P. J. Bach. Cannabis improves night vision a case study of dark adaptometry and scotopic sensitivity in kif smokers of the Rif mountains of northern Morocco. J Ethnopharmacol 2004 93(1) 99-104. D Souza, D. C., E. Perry, L. MacDougall, et al. The psychotomimetic effects of intravenous delta-P-tetrahydrocannab inol in healthy individuals implications for psychosis. Neuropsychophar-... 

The answer is c. (Hardman, p 527. Katzung, p 516.) Naloxone is a pure opioid antagonist at the (1, K, and 5 receptors. j,-receptor stimulation causes analgesia, euphoria, decreased gastrointestinal (Gl) activity, miosis, and respiratory depression. K-receptor stimulation causes analgesia, dysphoria, and psychotomimetic effects. 5-receptor stimulation is not fully understood in humans, but is associated with analgesia and antinociception for thermal stimuli. 

Although more stimulating antidepressants (e.g., bupropion, SSRIs, venlafaxine, or certain MAOIs) do not potentiate alcohol, they can produce insomnia. To minimize this problem, the dose may be given earlier in the day. TCAs may cause episodes of excitement (rare), confusion, or mania, usually in patients with an underlying psychotic illness, suggesting that a preexisting disorder must be present for these drugs to exert any psychotomimetic effects. 

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