Long-term treatment of chronic angina with nitrates is well established but
can be complicated by nitrate tolerance, or the rapid attenuation of antia
nginal effects, with continuous use. For therapy to be most effective, a ni
trate-free interval of 8 to 12 hours should be built into the dosing schedu
le. This article identifies optimal regimens for achieving 12-hour nitrate-
free intervals with various nitrate preparations and reviews the clinical t
rial evidence supporting selected regimens. Finally, guidance is provided o
n selecting nitrate preparations for formulary inclusion to allow for an ad
equate range of dosing options.