Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0028738 (nystagmus)
 7,431 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of alcohol and marijuana (tetrahydrocannabinol-THC) on saccades, smooth pursuit, and optokinetic nystagmus were quantitatively evaluated in 24 normal subjects using electro-oculographic recordings. Each subject was given an initial trial run and then tested three times (at weekly intervals) with either 0.0microgram THC or 100 microgram THC/kg bodyweight while at three different blood alcohol concentrations (0.0, 0.05 and 0.1%). A 2X3 factorial design was used. Saccades and smooth pursuit were induced by a dot of light moving in steps and ramps on a modified television set. Optokinetic nystagmus was induced by a cloth drum completely surrounding the subject and moving at a constant velocity of 30 degrees/s. Alcohol (0.05 and 0.1%) alone produced significant (p less than 0.05) impairment of saccade maximum velocity and reaction time, smooth pursuit velocity, and optokinetic slow-component velocity. The addition of THC caused performance to further deteriorate at each blood alcohol level but, in all but one instance, the added effect was not statistically significant ( greater than 0.05). At the THC and alcohol concentrations used in this study, the eye movement effects of alcohol over-shadowed those of marijuana.
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PMID:Effect of alcohol and marijuana on eye movements. 42 Jun 62

Although there are many roadside testing devices available for the screening of abused drugs, none of them can be used for the detection of ketamine, a popular abused drug in Hong Kong. In connection to local drug driving legislation, effective roadside detection of ketamine in suspected drug-impaired drivers has to be established. According to the drug evaluation and classification program (DEC), ketamine is classified in the phencyclidine (PCP) category. However, no study has been performed regarding the signs and symptoms exhibited by users under the influence of ketamine. In a study to develop a protocol for effective roadside detection of drug-impaired drivers, 62 volunteers exiting from discos were assessed using field impairment tests (FIT) that included measurements of three vital signs (i.e. body temperature, pulse rate and blood pressure), three eye examinations [pupil size, lack of convergence (LOC) and horizontal gaze nystagmus (HGN)] and four divided attention tests (Romberg, one-leg stand, finger-to-nose and walk-and-turn tests). Subsequent laboratory analysis of oral fluid and urine samples from the participants revealed the presence of common abused drugs in both the urine and oral fluid samples of 55 subjects. The remaining 7 subjects with no drug in their oral fluid samples were used as drug-free subjects. In addition, 10 volunteers from the laboratory who were regarded as drug-free subjects were also assessed using the same FIT. Among the 62 volunteers, 39 of them were detected with ketamine in their oral fluid. Of these ketamine users, 21 of them (54%) with only ketamine found in their oral fluid samples while the rest (18 subjects) of them had other drugs (i.e. MA, MDMA, benzodiazepines and/or THC) in addition to ketamine. Of the 21 ketamine-only users, 15 of them (71%) were successfully identified by FIT. It was found that when salivary ketamine concentrations were greater than 300 ng/mL, signs of impairment became evident, with over 90% detection rate using the FIT. By comparing the FIT observations on the 21 ketamine-only users with the drug-free subjects, the typical signs and symptoms observable for subjects under the influence of ketamine included LOC, HGN, elevated pulse rate and in general, failing the divided attention tests, especially the walk-and-turn and one-leg stand.
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PMID:Roadside detection of impairment under the influence of ketamine--evaluation of ketamine impairment symptoms with reference to its concentration in oral fluid and urine. 1704 88