Drug Administration Routes Overview

Drug Administration Routes

• A route of administration is the path a drug or substance takes to enter the body.

Factors Affecting Drug Route Choice

• Physical and chemical properties of the drug
• Site of desired drug action
• Absorption rate and extent from different routes
• Effect of digestive juices and first-pass metabolism
• Speed of desired response
• Dosage accuracy requirements
• Patient condition (health)

Classification of Drug Routes

• Local Routes: Used for localized treatment of lesions. System absorption is minimal. Common local routes include topical, deeper tissues, and arterial supply.
  • Topical: External application to the skin (e.g., ointments, creams).
  • Deeper tissues: Injection into deeper tissues (e.g., hydrocortisone acetate in a knee joint).
  • Arterial Supply: Injection directly into an artery; used for localized drug delivery (e.g., anti-cancer drugs or contrast media).
• Systemic Routes: Used to deliver a drug throughout the body.
  • Enteral Routes: Drugs are placed directly into the gastrointestinal (GI) tract (e.g., oral, buccal, sublingual, rectal).
  • Parenteral Routes: Drugs are administered by injection (e.g., intravenous, intramuscular, subcutaneous).

Enteral Routes

• Definition: Drugs are placed directly in the GI tract.
  • Oral Route: A drug is swallowed, and then absorbed in the stomach and small intestines.
    • Advantages: Safest, common, convenient, self-administered, cost-effective, and no sterilization required
    • Disadvantages: Slow absorption, delayed onset of action, not suitable for emergencies, unpalatable drugs, variable drug absorption, drug interactions with food, difficult administration in unconscious or uncooperative patients, and destruction by gastric secretions and extensive first-pass liver metabolism.
  • Sublingual/ Buccal Route: Drug is placed under the tongue (sublingual) or held in the mouth (buccal).
    • Advantages: Economical, drug absorption is quick, and first-pass metabolism is avoided.
    • Disadvantages: Drugs might be unpalatable, cause oral mucosa irritation, and large amounts may not be possible.

Explore the various routes of drug administration and the factors influencing their choice. This quiz covers local and systemic routes, including topical applications and deeper tissue injections. Understand how physical properties of drugs and patient conditions affect route selection.