Side effects of all these drugs vary but generally include nausea, constipation, headache, rapid heartbeat, and nasal congestion. In rare cases, they can cause hallucinations. Common side effects of benzodiazepines are daytime drowsiness and a hung-over feeling. Respiratory problems may be exacerbated. The drugs appear to stimulate eating and can cause weight gain.
Benzodiazepines are potentially dangerous when used in combination with alcohol.
Overdoses are serious, although very rarely fatal. Elderly people are more susceptible to side effects and should usually start at half the dose prescribed for younger people. Of great concern are studies showing automobile accidents and a high risk for hip fractures from falls in older people who take benzodiazepines. They are associated with birth defects, and should not be used by pregnant women or nursing mothers. The primary problem with these drugs is their loss of effectiveness over time with continued use at the same dosage.