Lanatoside C (or isolanid) is a cardiac glycoside, a type of drug that can be used in the treatment of congestive heart failure and cardiac arrhythmia (irregular heartbeat).

Lanatoside C can be used orally[1] or by the intravenous route.

[2] It is marketed in a number of countries and is also available in generic form.

[3] Its main indications are rapid response atrial fibrilation and paroxysmal supraventricular tachycardia,[citation needed] two common types of arrhythmia.

[4] The substance is composed of four monosaccharides (glucose, 3-acetyldigitoxose and two digitoxoses) and an aglycon named digoxigenin.