Summary
Three healthy subjects took methaqualone (1.0 mg/kg) once daily for 16 days. Equilibrium concentrations in plasma were established after multiple oral doses and there was a linear post-steady state decline in the log plasma concentration of methaqualone. The drug was also given as single oral doses and plasma concentrations were followed for 5 days (t1/2=36 to 38 h.). Sedative effects were studied by psychophysiological tests and subjective ratings both in the single and multiple dose experiments. A significant impairment of flicker fusion discrimination ability occurred during the increase in the plasma concentration of the drug; maximum effects preceded peak plasma concentrations and the impairment disappeared whilst plasma concentrations were still high. The same effects were found in the subjective ratings. The drug was shown to have a possible tremorogenic effect after a hypnotic dose. One subject experienced sedation during the multiple dose experiment, despite the use of a low dose, an observation that should be taken into account, e.g. in car driving.
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Alván, G., Ericsson, Ö., Levander, S. et al. Plasma concentrations and effects of methaqualone after single and multiple oral doses in man. Eur J Clin Pharmacol 7, 449–454 (1974). https://doi.org/10.1007/BF00560357
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DOI: https://doi.org/10.1007/BF00560357