[2][3] Contraindications include[3] Digitoxin exhibits similar toxic effects to digoxin, namely: anorexia, nausea, vomiting, diarrhea, confusion, visual disturbances, and cardiac arrhythmias.

[4] Drugs that can increase digitoxin toxicity include:[3] Drugs that can decrease the effectivity of digitoxin include:[3] Digitoxin inhibits the sodium-potassium ATPase in heart muscle cells, resulting in increased force of contractions (positive inotropic), reduced speed of electric conduction (negative dromotropic), increased excitability (positive bathmotropic), and reduced frequency of heartbeat (negative chronotropic).

[9] Marie Alexandrine Becker, a Belgian serial killer, was sentenced to death for poisoning eleven people with digitoxin.

In Metal gear Solid V the phantom pain, venom snake uses digitalis to obtain digoxin for tranquilizer rounds to incapacitate enemies.

[10][11] Digitoxin glycorandomization led to the discovery of novel digitoxigenin neoglycosides which displayed improved anticancer potency and reduced inotropic activity (the perceived mechanism of general toxicity).