Impaired driving

Antagonists. Most of the so-called Hi-antihistamines also block other receptors, including M-cholinoceptors and D-receptors. Hi-antihistamines are used for the symptomatic relief of allergies (e.g., bamipine, chlorpheniramine, clemastine, dimethindene, mebhydroline pheniramine) as antiemetics (meclizine, dimenhydrinate, p. 330), as over-the-counter hypnotics (e.g., diphenhydramine, p. 222). Promethazine represents the transition to the neuroleptic phenothiazines (p. 236). Unwanted effects of most Hi-antihistamines are lassitude (impaired driving skills) and atropine-like reactions (e.g., dry mouth, constipation). At the usual therapeutic doses, astemizole, cetrizine, fexofenadine, and loratidine are practically devoid of sedative and anticholinergic effects. Hj-antihistamines (cimetidine, ranitidine, famotidine, nizatidine) inhibit gastric acid secretion, and thus are useful in the treatment of peptic ulcers. 

Zolpidem was identified in the blood of 29 subjects arrested for impaired driving (19). In those in whom zolpidem was present with other drugs and/or alcohol, the symptoms reported were generally those of nervous system depression and included slow movements and reactions, slow and slurred speech, poor coordination, lack of balance,... 

In a comparison of cetirizine and loratadine, cetirizine 10 mg had acute sedative effects and impaired driving performance (65), whereas loratadine had no sedating potential furthermore, there was an additive effect of alcohol and cetirizine but not alcohol and loratadine. However, in a study using a driving simulator cetirizine 10 mg did not affect driving ability (66). In other studies cetirizine 20 mg caused significant sedation, while in one study there was a dose-dependent sedative effect with 10 mg and 20 mg but not 5 mg (67). Pooling the available data (SEDA-16, 163) shows that cetirizine is little more sedative than loratadine and terfenadine. 

In 104 cases carisoprodol and its metabolite meprobamate were detected in the blood of car drivers who were either involved in accidents or arrested for impaired driving (1). In many of these cases, either alcohol or other nervous system depressants were also found. In 21 cases cariso-prodol/meprobamate were the only drugs detected. Symptoms and reported driving behavior were similar in all cases. Impairment of driving ability appeared to be possible at any concentration of these two drugs. However, the most severe driving impairment and most overt symptoms of intoxication were noted when the combined concentration of carisoprodol and meprobamate exceeded 10 mg/1. 

Inhalation of 50 or 70% nitrous oxide in oxygen for 15 minutes impaired driving skill (25). Patients who receive nitrous oxide should be informed that its after-effects can alter their functioning without their being conscious of the fact (26). 

Terfenadine has been investigated in several thousands of patients and found to have a sedation rate comparable to placebo (5). It has not been shown to impair driving performance (6). 

Warning Use of the drug may impair driving capability (as in the Poisons Rule)... 

In a study conducted by the National Highway Traffic Safety Administration, a moderate dose of marijuana alone was shown to impair driving performance however, the effects of even a low dose of marijuana combined with alcohol were markedly greater than for either drug alone. Driving indices measured included reaction time, visual search frequency (driver checking of side streets), and the ability to perceive and/or respond to changes in the relative velocity of other vehicles. ... 

Impaired driving skills have been reported, although no clinically significantly adverse interactions have actually been reported. Alcohol may produce a slight (12%) increase in peak lithium levels. 

Diphenhydramine in doses of 25 or 50 mg was shown to increase the detrimental effects of alcohol on the performance of choice reaction and coordination tests in subjects who had taken 0.5 g/kg of alcohol. The interaction between diphenhydramine in doses of 50,75 or 100 mg and alcohol in doses of 0.5 to 0.75 g/kg has been confirmed in other reports. " " Emedasdne in oral doses of 2 or 4 mg twice daily was found to be sedating and impair driving ability in 19 healthy subjects. The addition of alcohol increased this impairment." A marked interaction can also occur with hydroxyzine" or promethazine. A very marked deterioration in driving skills was clearly demonstrated in a test of car drivers given 20 mL of Beechams Night Nurse (promethazine with dextrometh-... 

Banks, S., Catcheside, R, Lack, L., Grunstein, R. R., and McEvoy, R. D. 2004. Low levels of alcohol impair driving simulator performance and reduce perception of crash risk in partially sleep deprived subjects. Sleep 27 1063-1067. 

Employers should make road traffic safety a priority, enforcing policies that require use of safety belts and prohibit unsafe behaviors such as impaired driving and use of cell phones and other mobile devices that might distract the driver while the vehicle is in motion, the report concluded. 

Vehicle accidents, death from No seat belt use alcohol-impaired driving Seat belt use laws seat belt enforcement laws sobriety checkpoints reducing blood alcohol concentration to 0.08% minimum legal drinking age laws... 

Drinking dulls your ability to make decisions. Even small amounts of alcohol impair driving ability. In your body, alcohol quickly enters the bloodstream from the stomach because it doesn t have to be digested. As it circulates through the body, it reaches the brain where it slows down functioning and acts to depress the central nervous system. The liver is able to break down the alcohol at a rate of about one ounce per hour. Alcohol in excess of that amount stays in the bloodstream and affects numerous critical brain functions ... 

A large body of evidence demonstrates that interacting with in-vehicle devices while driving can impair driving performance on a number of safety critical measmes. But does this degradation in driving performance translate into an increase in crashes and crash risk A number of studies have been conducted to examine this question. 

Peterson BL. Prevalence of gabapentin in impaired driving cases in Washington State in 2003-2007. J Anal Toxicol 2009 33(8) 545-9. 

In six cases involving drivers arrested for driving under the influence who subsequently tested positive for toluene, blood toluene concentrations were 12-45 mg/1 [98 ]. All were intoxicated, and had symptoms that included balance problems, confusion and disorientation, loss of coordination, and inability to follow instructions. They also had horizontal nystagmus but not vertical nystagmus, tachycardia and raised blood pressure, and reduced body temperature. These findings are consistent with prior reports that subjects with blood toluene concentrations above 10 mg/1 have impaired driving skills. 

Dept of Transportation (US), National Highway Traffic Safety Administration (NHTSA). Traffic safety facts 2013 data alcohol-impaired driving. (Washington, DC) NHTSA 2014. [Cited 18.05.15.] Available at http //www-nrd.nhtsa.dot.gov/Pubs/812102.pdf. 

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