General and Systematic Veterinary Pharmacology

ALKALOIDS

• Alkaloids are nitrogenous substances obtained from various parts of the plant. Alkaloids containing oxygen are solids and comparatively non volatile (cocaine) while those that do not contain oxygen are liquids and volatile (nicotine, lobeline and coniine).
• Alkaloids are insoluble in water while their salts (atropine sulphate, caffeine citrate) are soluble in water.
• Alkaloids are bitter to taste. They are incompatible with the alkalies, tannic acid and heavy metals.
• Alkaloids represent the waste products of plant metabolism and their names end with ‘ine’.
• Alkaloids should be administered in small quantities and when given in excess they may produce death without much postmortem changes for diagnosis. (Adrenaline is considered as animal alkaloid).