| Digoxin, also known as digitalis, is a cardiac glycoside. Its corresponding aglycone is digoxigenin, and its acetyl derivative is acetyl digoxin. |
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| Digoxin is white color, odorless bitter in taste Powder. It is soluble in methanol, insoluble in cold water and acetone. Its chemical formula is (3beta,5beta,12beta)-3-((o-2,6-dideoxy-beta-d-ribo-hexapyranosyl-(1-4)-2,6-dide;-12,14-dihydroxycard-20(22)-enolide;14-dihydroxy(3beta,5beta, 12beta)-xopyranosyl)oxy]-1;14-dihydroxy-,(3beta,5beta,12beta)-y)-1;-2,6-dideoxy-beta-d-ribo-hexopyranosyl-(1.fwdarw.)-2,6-dideoxy-beta-d-ribo-he;acygoxin;card-20(22)-enolide,3-((o-2,6-dideoxy-beta-d-ribo-hexopyranosyl-(1-4)-o-2,6-di;card-20(22)-enolide,3-[(o-2,6-dideoxy-beta-d-ribo-hexopyranosyl-(1.fwdarw.)-o;cardoxin; chloroformicdigitalin;cordioxil; davoxin;deoxy-beta-d-ribo-hexopyranosyl-(1-4)-2,6-dideoxy-beta-d-ribo-hexopyranosyl)ox and molecular formula is C41H64O14. |
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| Digoxin is widely used in the treatment of various heart conditions, namely atrial fibrillation, atrial flutter and sometimes heart failure that cannot be controlled by other medication. |
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| Source |
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| Digoxin is extracted from the foxglove plant, Digitalis lanata. |
| Digitalis lanata (often called the Woolly Foxglove or Grecian Foxglove) is a species of foxglove that is part of the Plantaginaceae family.
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| The plant commonly grows from 0.3 to 0.6 meters in height, or about 13 to 26 inches. The plant prefers part shade and humus rich soil. It can grow under dry or moist conditions. The elongated leaves are mid–green, wooly, veined, and covered with white hairs on the underside. They also have a very bitter taste. There is a tidy rosette before the spike goes up, and it is neatly arranged around the purple-tinged stems.
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| Digitalis lanata is found mostly in Eastern Europe. The plant can now be found throughout the world, growing in woodland areas, on roadsides, and in mountainous regions. In North America, it can be found mostly in the Northeast and Southwest regions. It is cultivated mainly in New York, Washington, Utah, and Colorado. |
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| Pharmacology |
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| Digoxin has two effect on heart: |
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| Mechanical effect (positive inotropic) |
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| Inhibits the sarcolemmal Na+/K+ ATP ase pump, increasing intracellular sodium, which through an exchange protein leads to increased calcium in the sarcoplasmic reticulum |
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| This in turn results in greater amounts of calcium being released to the myofilaments with each electrical excitation, thereby enhancing the force of each contraction. |
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| Electrical effect (negative chronotropy) |
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| Digoxin affects cardiac tissue electrical properties directly, and also modifies autonomic nervous system activity, increasing vagal tone and decreasing sympathetic activity. |
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| Decreases AV nodal conduction velocity, and enhances the refractory period, therefore reducing transmission of atrial impulses to the ventricles. |
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| Dosage |
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| Tachycardial atrial fibrillation : Oral 0.25 mg T.I.D(Initial Loading Dose for 1to 3 days) than Maintenance dose 0.125 mg to 0.5mg OD. |
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| Emergency Therapy |
| 0.125 mg to 0.5 mg I.V. in every 6 hours |
