7.1.3 Impairments associated with medication
Medications prescribed for treating psychiatric conditions may impair driving performance. There is, however, little evidence that medication, if taken as prescribed, contributes to crashes; in fact, it may even help reduce the risk of a crash (refer to Part A section 2.2.8 Drugs and driving). Numerous psychotropic medications have been shown to impair perception, vigilance and psychomotor skills. Many medications can produce side effects such as sedation, lethargy, impaired psychomotor function and sleep disturbance. Benzodiazepines have especially been shown to impair vision, attention, information processing, memory, motor coordination and combined-skill tasks. Tolerance to the sedating effects may develop after the first few weeks, although other cognitive impairments may persist. The assessment of medication effects should be individualised and rely upon self-report, observation, clinical assessment and collateral information to determine if particular medications might affect driving. Health professionals should have heightened concern when sedative medications are prescribed but should also consider the need to treat psychiatric conditions effectively. Refer also to section 9 Substance misuse (including alcohol, illicit drugs and prescription drug misuse).