Pharmacognosy of Cardiotonics

  • The pharmacological agents which provides strength to the cardiac muscles and improve its force of contraction are called as “Cardiotonics” and are employed in the treatment of CCF “Congestive Cardiac Failure”.
      • e.g.


  • Synonyms: Digitalis Leaves, Foxglove Leaves.
  • Biological Source: Digitalis consists of dried leaves of the plant known as “Digitalis purpurea” belonging to the family “Scrophulariaceae”, leaves are dried below 60 0 C and should contain NMT 5% moisture.
  • Geographical Distribution: Its cultivated majorly in European countries like England, France and also in United States. In India its production is limited to the certain parts of Kashmir.
  • Organoleptic Characters:
Color Dark Greyish Green
Odor Slight
Taste Bitter
Size 10-40 cm L X 4-20 cm W.
Shape Broadly Ovate, irregular crenate margins

Extra Features:  Leaves are pubescent on both the surfaces with pinnate venation and prominent veinlets on lower sides.
  • Chemical Constituents:
    • Digitalis contains “Cardiac Glycosides” (Cadenolides) as active constituents of the drug.
    • The chief active constituents of the Digitalis are,
            • Purpurea Glycoside A
            • Purpurea Glycoside B.
    • Purpurea Glycoside A on enzymatic hydrolysis produce-----> Digitoxin + Glucose, Digitoxin on further hydrolysis produce--------> Digitoxigenin + Digitoxose.
    • Purpurea Glycoside B on enzymatic hydrolysis produce-----> Gitoxin + Glucose, Gitoxin on further hydrolysis produce--------> Gitoxigenin + Digitoxose.
    • Other minor glycosides of Digitalis include,
            • Gitaloxin.
            • Gluco-gitaloxin.
            • Verodoxin.
            • Gluco-verodoxin
            • Odoroside H.
    • Digitalis also contains two saponins,
            • Digitonin.
            • Gitonin.
    • Digitalis also contains certain hydrolytic enzymes. (Hence should contain moisture content NMT 5% to avoid decomposition of the glycosidic activities of the drug.
  • Uses:
  1. As Cardiotonic in treatment of CCF.
  2. As diuretic.
  3. Major Disadvantage: Cumulative effect hence dose monitoring is necessary.

Chemical Tests:

  1. Keller-Killiani Test for Digitoxose:
    1. Boil the powdered drug with 10ml of 70% alcohol for 3 mins.
    2. Extract is filtered.
    3. To the filtrate add 5 ml water and 0.5 ml of Strong Solution of Lead Acetate.
    4. Filter.
    5. To the filtrate add equal volume of Chloroform and evaporate to yield dried extractive.
    6. Dissolve the dried extractive in Glacial Acetic Acid and add few drops of Ferric Chloride Solution to it.
    7. Transfer above content to a test tube containing 2ml Conc. Sulphuric acid.
    8. A reddish brown layer changing to bluish green color on standing is observed.
    9. Digitoxose Confirmed.


  • Synonyms: Arjun, Arjuna Bark.
  • Biological Source: Arjuna consists of dried bark of the plant known as “Terminalia arjuna” belonging to the family “Combrataceae”.
  • Geographical Distribution: Indigenous to India and is also cultivated in nearby Asian countries. In India most common in Maharashtra particularly in Nagpur and Dehradun.
  • Organoleptic Characters:
ColorOuter Side: Greyish Brown.
Inner Side: Reddish Brown with striations.
Size Pieces of various size.
ShapeFlat, Fracture Short

  • Chemical Constituents:
    • Arjuna mainly contains Tannins upto 15% and :Triterpenoid saponins as active constituents.
    • The chief active constituents of the drug are,
      • Arjunolic acid.
      • Arjunic acid.
      • Arjunogenin.
    • Other constituents of the drug are,
      • B- Sitosterol.
      • Ellagic acid.
      • Flavonoids.
      • Salts of Aluminium, calcium and magnesium.
    • Starch, proteins and fats are inert constituents of the drug.
  • Uses:
  1. As Cardiotonic
  2. As Diuretic.
  3. Antidysenteric.
  4. Hypotesnsive.
  • Chemical Test:
  • Ether extract shows pinkish fluorescence under UV light.

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