Digitalis is a genus of about 20 species of herbaceous perennial plants, shrubs, and biennials, commonly called foxgloves. Digitalis is native to Europe, Western Asia, and northwestern Africa. The flowers are tubular in shape, produced on a tall spike, and vary in color with species, from purple to pink, white, and yellow. The scientific name means "finger".

Digitalis is also a medicine used to treat certain heart conditions, such as congestive heart failure (CHF) and heart rhythm problems (atrial arrhythmias). It can increase blood flow throughout the body and reduce swelling in the hands and ankles. Digitalis directly increases the contractile power of the heart muscle, enabling a disease-weakened heart to keep up with the body’s demand for heart action. It is a cardiac glycoside, which means it strengthens the contractions of the heart muscle.

Digitalis toxicity can be a side effect of digitalis therapy, which can occur when you take too much of the drug at one time or when levels of the drug build up for other reasons such as other medical problems you have. Symptoms of digitalis toxicity include nausea, vomiting, diarrhea, confusion, and changes in vision.

Other important information about digitalis includes:

• Digitalis is an example of a drug derived from a plant that was formerly used by herbalists; herbalists have largely abandoned its use because of its narrow therapeutic index and the difficulty of determining the amount of active drug in herbal preparations.
• Other medicines that you may be taking can increase or decrease the effect of digitalis. These effects are called an interaction.
• Blood tests should be done to check for conditions that make digitalis toxicity more common.

In summary, digitalis is a genus of plants commonly called foxgloves, and it is also a medicine used to treat certain heart conditions. It is a cardiac glycoside that strengthens the contractions of the heart muscle. Digitalis toxicity can be a side effect of digitalis therapy, and it is important to have blood tests done to check for conditions that make this toxicity more common.