Midazolam dosage studies in institutionalized geriatric patients.

Three different dosage studies were carried out with midazolam in 47 institutionalized geriatric patients (17 males: mean age 82.9 years; 30 females: mean age 81.3 years) who were suffering from insomnia of long standing. Study I investigated the hypnotic efficacy of midazolam versus placebo in a double-blind, cross-over trial comparing the 7.5 and 15 mg doses of midazolam in 18 subjects. Both midazolam doses shortened sleep onset latency by 40 min (15 mg) and 31 min (7.5 mg). Both doses increased total sleep time compared with placebo. In study II, a comparative, cross-over trial in 10 subjects, an initial dose of 7.5 mg midazolam was sufficient to reduce the subjective appreciation of sleep onset time to less than 60 min on 66 of 70 study nights. Oxazepam (25 mg) had a comparable favourable effect but less frequently (53 of 70 nights). In study III, individual dose limits were investigated in 19 insomniac patients. The minimum effective dose was 7.5 mg. The maximum tolerated dose was in the range 15 to 52.5 mg according to the subjects' assessment. The most common optimum dose was 15 mg (10 of 19 patients). The higher doses prolonged sleep but midazolam appears to have a wide margin of safety as residual sedative effects appeared only after very high doses (four of 19 for 30 mg; eight of 19 for 37.5 mg). In some patients, 7.5 mg was the minimum dose that was effective in shortening sleep latency.(ABSTRACT TRUNCATED AT 250 WORDS)