Pharmaceutical hydrogel formulations containing polyvinyl alcohol are
provided. The formulations may serve as rug reservoirs in electrotransport
drug delivery systems or passive transdermal systems, or they may be used
in a variety of other types of dosage forms, e.g., capsules,
suppositories, aerosols, and the like. With these formulations, there is
virtually no syneresis encountered upon long term storage, an advantage
that derives from selecting the quantity of polyvinyl alcohol in the gel
to correspond to the polymer's degree of hydrolysis.