Drug Sources & Classification Quiz

Drug Sources & Classification

• Drugs are broadly classified by origin (natural or synthetic).

• Natural origin drugs come from plants, animals, or minerals.

• Plant-based drugs (e.g., Reserpine from Rauwolfia, digoxin from foxglove).

• Animal-origin drugs (e.g., thyroid extract, insulin from pancreas).

• Mineral-origin drugs (e.g., iron salts for anemia).

• Synthetic drugs are chemically manufactured.

• Chemical products (e.g., sodium chloride, potassium permanganate - synthetic).

• Pharmaceutical chemistry products (e.g., isoniazid, ibuprofen).

• Antibiotics (e.g., penicillin, streptomycin - produced by microorganisms).

• Vitamins (e.g., vitamin C, B vitamins).

• Organ drugs (e.g., thyroid extract, insulin from organs or tissues).

• Serums and vaccines (antitoxins and vaccines are produced by various labs and institutions.)

• Drugs can also be classified by:

  • Origin
  • Mechanism of action
  • Pharmaceutical form
  • Physical state
  • Method of preparation
  • Description and use of the pharmaceutical form
  • Site of action
  • Route of administration
  • Effect
  • Formulation and preparation
  • According to pharmaceutical references by therapeutic groups

Drug Classification by Origin

• Natural Origin Drugs (Natural Sources):
  • Plant Origin: Plants are a significant source of medicines. Medicinal plants can be used as-is or, following extraction and processing, turned into modern medicines, using various pharmaceutical forms such as tablets, capsules, and syrups. Examples include:
    • Reserpine, used as a tranquilizer and hypotensive agent, is isolated from the Rauwolfia plant.
    • Digoxin, a cardiac stimulant, is derived from the foxglove plant.
    • Morphine, a strong analgesic and opioid, is extracted from the opium poppy.
  • Animal Origin: Animals are a valuable source for drug production. Examples include:
    • Insulin, a life-saving hormone derived from the pancreas.
    • Thyroid extract, a crucial hormone supplement.
    • Hormones (e.g., growth hormone) extracted from various animal glands.
    • Reserpine and digoxin
  • Mineral Origin: Minerals and related substances can be used medicinally. Examples include:
    • Iron salts (used to treat anemia).
    • Petroleum derivatives (e.g., paraffin oil, Vaseline).

Plant-Derived Drugs

• Plants are valuable in drug production. They're used as-is or chemically processed into various pharmaceutical forms like tablets or capsules.
• Extracts from plants such as periwinkle (Vinca rosea), have medicinal properties.
• Vinblastine and vincristine from Periwinkle are antitumor agents used for specific cancers.
• Paclitaxel (Taxol) from the Pacific yew tree is used for ovarian cancer.
• Other plant-derived drugs include various roots, flowers, and fruits

Semi-Synthetic Drugs

• Some drug components may be initially inactive but can be chemically modified to become active.
• For instance, Mexican yams contain steroid-like compounds chemically modified into cortisone and estrogens.

Animal-Origin Drugs

• Animal-derived drugs also include many substances such as pepsin (from mammals) for indigestion and heparin (from animal tissue) to treat blood clotting.
• Other materials, including bee products, animal secretions (e.g., musk) are used by doctors as part of a balanced health profile.

Pharmaceutical Dosage Forms

• Drug delivery systems include powders, granules, capsules, tablets, pills, and more.
• Dosage forms can be solid, liquid, or semi-solid.

Importance of Dosage Forms

• Dosage forms enhance drug safety and effectiveness.
• Proper dosage forms allow for accurate dosing, masking unpleasant tastes or smells, protecting drugs from environmental factors, and delivering consistent action.

Factors Affecting Drug Selection

• Bioavailability and bioequivalence
• Target effect desired
• Route of administration
• Side effects
• Elimination time-frame
• Cost-effectiveness
• Patient acceptance of the drug form

Routes of Drug Administration

• Oral Route: Most common, easy, and safe method but variable absorption.

• Parenteral Routes: Intravenous, intramuscular, subcutaneous, and others. Faster, but riskier than oral and requires medical expertise.

  • Advantages: rapid onset, bypasses liver metabolism, suitable for unconscious patients, and those with compromised GI systems.
  • Disadvantages: invasive, potential for tissue damage, and complications.

• Topical Routes: Applied locally for surface effects.

  • Commonly used for skin conditions, eye issues, or nose and ear use.
  • Advantages: avoids systemic effects, good for localized treatments.
  • Disadvantages: slower absorption compared to systemic routes.

• Rectal and Vaginal Routes: For localized effects or situations where oral isn't possible.

• Sublingual and Buccal Routes: For immediate effect by placing drugs under the tongue or between cheek and gum, to quickly access the bloodstream avoiding liver metabolism.

Drug Classification: Solid, Liquid, Semi-Solid

• Solid dosage forms: powders, granules, capsules, tablets, pills, lozenges
• Liquid dosage forms: solutions, syrups, elixirs, suspensions, emulsions, lotions, gargles, drops.
• Semi-solid dosage forms: ointments, creams, gels, suppositories

Factors Affecting Drug Absorption

• Effect of food and other medications
• Chemical and physical properties of the drug
• Rate of gastric emptying

General Principles for Drug Preparation

• All ingredients should be compatible and safe.
• Stable under storage conditions.

Test your knowledge on drug sources and classification methods. This quiz covers the origin of drugs, including natural and synthetic sources, as well as various classification criteria like mechanism of action and pharmaceutical form. Challenge yourself and discover how well you understand pharmacology!