Psychopharmacology
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Randomized Controlled Trial Comparative Study Clinical Trial
Comparing the subjective, psychomotor, and physiological effects of intravenous hydromorphone and morphine in healthy volunteers.
The psychopharmacological profile of hydromorphone, an opioid that has been used extensively for many years for post-operative pain management, has not been adequately characterized in non-drug abusers. ⋯ The results of this study demonstrate that 0.33-1.3 mg hydromorphone had orderly, dose-related effects on subjective, psychomotor, and physiological variables, and similar effects to those of a benchmark mu opioid agonist, morphine.
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Randomized Controlled Trial Clinical Trial
A naturalistic investigation of the effects of day-long consumption of tea, coffee and water on alertness, sleep onset and sleep quality.
The effects of caffeine, especially caffeinated coffee, on human performance have been extensively studied. However, few studies have been naturalistic representations of how tea/coffee is normally consumed in terms of dose and time of consumption. ⋯ These results indicate that ingestion of caffeinated beverages may maintain aspects of cognitive and psychomotor performance throughout the day and evening when caffeinated beverages are administered repeatedly. This study also demonstrates that day-long tea consumption produces similar alerting effects to coffee, despite lower caffeine levels, but is less likely to disrupt sleep. Other differences between tea and coffee were more subtle, and require further investigation.
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Randomized Controlled Trial Multicenter Study Clinical Trial
Double blind study of tiapride versus haloperidol and placebo in agitation and aggressiveness in elderly patients with cognitive impairment.
The aim of the present study was to compare the efficacy and safety of tiapride versus haloperidol and placebo in the treatment of agitation and aggressiveness in elderly patients with mild or moderate mental impairment. ⋯ Tiapride is not different from haloperidol in the treatment of agitation and aggressiveness in elderly patients and better tolerated, in particular with significantly fewer extrapyramidal symptoms.
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Randomized Controlled Trial Clinical Trial
Comparison of the effects of venlafaxine, paroxetine and desipramine on the pupillary light reflex in man.
The time-course of the pupillary light reflex response is determined by the successive activation of the parasympathetic and sympathetic innervations of the iris, the latency and the amplitude reflecting parasympathetic and the recovery time mainly sympathetic activity. ⋯ The increase in resting pupil diameter could be indicative of parasympathetic inhibition and/or sympathetic activation. The shortening of the recovery time of the light reflex response is consistent with sympathetic potentiation resulting from noradrenaline uptake blockade in the iris. The prolongation of the latency and decrease of the amplitude of the light reflex response are indicative of a parasympatholytic effect of venlafaxine. However, as venlafaxine has negligible affinity for muscarinic cholinoceptors, this effect cannot be attributed to the blockade of cholinoceptors in the iris. A possible explanation for this finding is that it reflects a central rather than a peripheral effect of the drug: the blockade of noradrenaline uptake in the brain could lead to the potentiation of the noradrenergic inhibition of central parasympathetic (Edinger-Westphal) neurones. These results demonstrate the ability of therapeutically relevant single doses of venlafaxine to potentiate noradrenergic responses in man, consistent with the blockade of noradrenaline uptake.
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Randomized Controlled Trial Clinical Trial
Subjective, psychomotor, and analgesic effects of oral codeine and morphine in healthy volunteers.
The subjective, psychomotor, and physiological effects of analgesic doses of oral codeine and morphine were examined in 12 healthy volunteers. Subjects ingested placebo, morphine 20 or 40 mg, or codeine 60 or 120 mg in a randomized, double-blind, crossover design. The smaller and larger doses of each drug were putatively equianalgesic, and the cold-pressor test was included to test this assumption. ⋯ Plasma codeine and morphine levels varied as an orderly function of dose. These results suggest that oral codeine and morphine are appropriate drugs for outpatient pain relief because they are effective analgesics at doses that have only modest effects on mood, produce few side effects, and do not impair performance. The results also suggest a possible ceiling effect of codeine on analgesia and subjective effects.