Bioavailability of ergoloid mesylates liquid capsule.

Bioavailability of two formulations of ergoloid mesylates was compared in 18 healthy men. In a randomized, crossover design, each subject received a single oral dose of six liquid capsules and six oral tablets, each capsule or tablet containing 1 mg of the active ingredient. A one-week washout period intervened between the two doses. Blood samples were drawn at intervals up to ten hours after drug ingestion and were assayed for plasma concentrations of ergoloid mesylates by a specific radioimmunoassay. The liquid capsule produced mean peak concentrations and areas under the curve (AUC) that were about 12% higher than those produced by the oral tablet; these differences were statistically significant (P less than 0.05). No statistically significant differences were observed for the other pharmacokinetic parameters, namely, time to peak concentration, apparent rate constants for absorption and elimination, and lag time. As the differences in peak concentration and AUC were less than 20%, even though they were statistically significant, the two formulations were considered bioequivalent according to FDA guidelines for bioequivalence. The therapeutic benefit that might derive from greater bioavailability of the liquid capsule has not been established.