In three of these studies there was a significantly greater improvement with Cyclobenzaprine hydrochloride tablets, USP than with diazepam, while in the other studies the improvement following both treatments was comparable.
Although the frequency and severity of adverse reactions observed in patients treated with Cyclobenzaprine hydrochloride tablets, USP were comparable to those observed in patients treated with diazepam, dry mouth was observed more frequently in patients treated with Cyclobenzaprine hydrochloride tablets, USP and dizziness more frequently in those treated with diazepam.
The incidence of drowsiness, the most frequent adverse reaction, was similar with both drugs.
Cyclobenzaprine is eliminated quite slowly, with an effective half-life of 18 hours (range 8-37 hours; n=18); plasma clearance is 0.7 L/min.
The plasma concentration of Cyclobenzaprine is generally higher in the elderly and in patients with hepatic impairment.
Eight double-blind controlled clinical studies were performed in 642 patients comparing Cyclobenzaprine hydrochloride tablets, USP 10 mg, diazepam**, and placebo.
Muscle spasm, local pain and tenderness, limitation of motion, and restriction in activities of daily living were evaluated.
In light of these findings, therapy with Cyclobenzaprine hydrochloride tablets, USP in the elderly should be initiated with a 5 mg dose and titrated slowly upward.