Digitalis

Digitalis (or Digoxin) is a poisonous substance that appears naturally in the flower Digitalis or Foxglove. A group of medicines extracted from the flower is called digitalin and used for treating heart conditions. It can be administered either orally or by injection into a vein.

Characters poisoned with digitalis

 * Mrs Boynton - Appointment with Death
 * Mary Jordan - Postern of Fate
 * Sylvia Keene - The Herb of Death
 * Janet Rowe - Crooked House