Tanshinol has desirable antianginal and pharmacokinetic properties and is a key compound of Salvia miltiorrhiza roots (Danshen).The reported effective concentrations of tanshinol in vitro are higher (3-100 times) than human maximum plasma concentrations of tanshinol after dosing the Danhong injections at clinical dose level;the reported effective doses of tanshinol in rats also exceed (5-10 times) the rat dose of tanshinol derived from the clinical dose.Matching its levels of systemic exposure after dosing to its effective concentration for the antianginal activities most likely results in better translation of its pharmacological properties to the overall antianginal effect of Danshen therapy.This requires having a way to manipulate the post-dose concentration of tanshinol.Dosage adjustment and drug combination are commonly used to change drug concentration in blood.These may, however, raise some safety concerns.A therapeutically useful method should be both effective(large potential to increase concentration) and safe (such as with very little or no dose-related toxicity).Elimination is often a major determinant of drug concentration after dosing.Renal excretion is the predominant route of elimination of tanshinol in humans and rats, attributed mainly to active tubular secretion.