How This Helps
The active principles digoxin and digitalin act as a powerful cardiotonic and a positive inotropic agent, having a favorable result on the muscular contractions of the heart.  Digitalis Purpurea acts by inhibiting the sodium-potassium ATPase action driving sodium ions out of the cell and facilitating calcium ions into the cell. This increases the cytoplasmic calcium which in turn improves the cardiac contractility.  An improved contractility means a better cardiac output and better survival. Digitalis drug also has a stimulating action on the parasympathetic nervous system which helps in correcting cardiac arrhythmias like atrial fibrillation by regulating the heart rate. The diuretic action of digitalis flushes out excess fluid in the body through urine reducing the workload on the heart considerably. 
Science and Research
Heart diseases are a result of error in diet and lifestyle, mental stress and systemic causes like diabetes, hypertension, obesity, and genetic tendency. Homoeopathy helps defeat mental stress which is a leading cause of heart attacks. The formation of plaques in arteries of the heart causing blockage and decreased blood supply, eventually leads to injury or death of the heart muscle better understood as angina and heart attack respectively. Injury to the heart muscle gradually leads to decreased output of the heart affecting rest of the organs and their blood supply. Homoeopathy has a vital role to play in protecting the heart to prevent repeated insults to the cardiac tissue and improve the quality of life.
Digitalis purpurea, commonly known as the foxglove is a well indicated, unparalleled medicine used in various heart diseases. The extract used to prepare homoeopathic medicines is obtained from the leaves of the plant.
The use of digitalis purpurea especially in the geriatric group helps in building up secondary compensation mechanisms of the cardiac unit reducing hospitalizations and clinical deterioration significantly. 
Digitalis 30C, 6pills 3 times a day for at least 3 months or till the heart rate stabilizes. The tincture is better used as a palliative in heart failure in the form of 20 drops diluted in small quantity of water twice a day.
Note: For patient specific treatments and dosage, always consult with a homeopathic doctor before beginning treatment and taking digitalis purpurea.
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2. Sharma A, Purkait B. Identification of Medicinally Active Ingredient in Ultradiluted Digitalis purpurea: Fluorescence Spectroscopic and Cyclic-Voltammetric Study. J Anal Methods Chem. 2012;2012:109058. doi: 10.1155/2012/109058. Epub 2012 Mar 26.
3. Rain C, Rada G. Is there a role for digitalis in chronic heart failure?–First update. Version 2. Medwave. 2015 Jun 5 [revised 2015 Jun 5];15 Suppl 1:e6148. doi: 10.5867/medwave.2015.6149. English, Spanish.
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