Best filler for a 2-mg testosterone capsule?

Testosterone has limited bioavailability when administered orally, chiefly due to its degradation; hence the development of methyltestosterone. Several approaches seem to limit this degradation, according to the literature. The formulations include incorporation of the testosterone in oil to be encapsulated and the use of Methocel E4M Premium with other excipients such as lactose.

In either approach, ?protection? of the testosterone is provided by the named excipient. In the case of Methocel E4M Premium, a ?delayed-release? effect has been reported in the literature.This is not a ?time-release? dose form, because the drug release appears to be dependent upon erosion of the Methocel E4M Premium ball formed upon capsule dissolution, which varies with gut motility and contents.

Alternative dosage forms that bypass gastric degradation of the testosterone include incorporation of the active ingredient in troches, sublingual drops, and penetration-enhanced topical gels and vanishing creams.