Drug Administration Routes

Understanding the various ways drugs are administered is crucial for effective treatment, impacting absorption, onset of action, and potential side effects. Each route has specific advantages and disadvantages.

Core Principles

• Oral Route: Most common, convenient, but slow onset and absorption can be irregular.
• Sublingual Route: Rapid absorption directly into bloodstream, bypasses GI tract.
• Parenteral Routes (Injections): Rapid onset, bypasses GI tract, but requires sterile technique and skilled administration.
• Inhalation: Rapid absorption for respiratory conditions.
• Local Application: Targeted effect at the site of application.
• Rectal Route (Enema): Useful for local effects or when oral route is not feasible.

Action Steps

• Assess patient condition (consciousness, emergencies, GI status).
• Consider drug properties (irritation, stability in GI tract, required onset speed).
• Select the most appropriate route based on efficacy, safety, and convenience.
• Ensure correct dosage and administration technique for the chosen route.
• Monitor for desired effects and potential adverse reactions.

Key Terms

• Oral Route: Drug taken by mouth and swallowed, absorbed from the GI tract.
• Sublingual Route: Drug placed under the tongue for rapid absorption into the bloodstream.
• Parenteral Route: Administration by injection (e.g., IV, IM, SC, ID), bypassing the GI tract.
• Inhalation Route: Drug administered as a gas or vapor into the lungs.
• Local Application: Drug applied topically to skin or mucous membranes.
• Rectal Route: Drug administered via enema or suppository.
• Bioavailability: The rate and extent to which an active drug concentration is available at the site of action.

Real World Examples

• Emergency treatment for anaphylaxis.: Intravenous (IV) injection for rapid onset.
• Managing chronic pain.: Oral tablets or capsules for convenience and sustained release.
• Treating angina.: Sublingual nitroglycerin for rapid relief.
• Asthma treatment.: Inhaled bronchodilators for direct action on the lungs.
• Skin infection.: Topical ointment for localized treatment.

Timeline

• Ancient Times: Oral administration (herbs, potions) and topical applications were primary methods.
• 19th Century: Development of hypodermic needles led to widespread use of subcutaneous and intramuscular injections.
• Early 20th Century: Intravenous administration became more common, allowing for precise dosing and rapid effects.
• Mid-20th Century: Inhalational therapy advanced with metered-dose inhalers and nebulizers.
• Late 20th Century - Present: Development of transdermal patches, sustained-release formulations, and targeted drug delivery systems.

People

• Alexander Fleming: Discovered Penicillin in 1929.