This document provides a comprehensive overview of the various routes of drug administration, including oral, intravenous, intramuscular, subcutaneous, topical, inhalation, rectal, and transdermal methods. It discusses the advantages and disadvantages of each route, their impact on bioavailability,...
Routes of administration
1. Topical Route
Description:
Topical administration involves applying a drug directly to the surface of the skin or mucous
membranes for localized effects. This route is commonly used for dermatological treatments,
such as creams, ointments, and lotions.
Mechanism:
Drugs administered topically are intended to act locally on the skin or the mucous membranes,
though some drugs can be absorbed into the bloodstream for systemic effects.
Applications:
● Treatment of skin conditions (e.g., eczema, psoriasis, infections).
● Pain relief using topical anesthetics.
● Delivery of anti-inflammatory or antifungal agents.
Advantages:
● Direct application to the affected area.
● Minimizes systemic side effects.
● Non-invasive and easy to use.
● Suitable for self-administration.
● Prolonged drug action at the site of application.
Disadvantages:
● Limited to conditions affecting the skin or mucous membranes.
● Absorption can be unpredictable.
● Potential for skin irritation or allergic reactions.
● May require frequent application.
● Some drugs may not penetrate deeply enough to be effective.
2. Oral Route (PO)
Description:
The oral route is the most common method of drug administration, where the drug is swallowed
and absorbed through the gastrointestinal tract.
Mechanism:
After ingestion, the drug passes through the stomach and into the intestines, where it is
absorbed into the bloodstream. It then undergoes first-pass metabolism in the liver before
reaching systemic circulation.
Applications:
● Most medications, including antibiotics, pain relievers, and supplements.
, ● Ideal for chronic conditions requiring long-term treatment.
Advantages:
● Convenient and easy to administer.
● Non-invasive and generally safe.
● Suitable for self-administration.
● Wide variety of dosage forms available (tablets, capsules, liquids).
● Slow, controlled release options available.
Disadvantages:
● Variable absorption depending on food, pH, and gastrointestinal motility.
● First-pass metabolism in the liver can reduce drug effectiveness.
● Not suitable for patients who are vomiting or unconscious.
● Some drugs can irritate the gastrointestinal tract.
● Onset of action is slower compared to other routes.
3. Sublingual Route
Description:
Sublingual administration involves placing a drug under the tongue, where it dissolves and is
absorbed directly into the bloodstream.
Mechanism:
The rich blood supply under the tongue allows for rapid absorption of the drug, bypassing the
gastrointestinal tract and first-pass metabolism in the liver.
Applications:
● Medications requiring rapid onset of action (e.g., nitroglycerin for angina).
● Drugs that are unstable or poorly absorbed in the gastrointestinal tract.
Advantages:
● Rapid absorption and onset of action.
● Bypasses first-pass metabolism.
● Easy and convenient to use.
● Suitable for patients who have difficulty swallowing.
● Useful for emergencies (e.g., angina attacks).
Disadvantages:
● Limited to drugs that are effective in small doses.
● Not suitable for drugs with an unpleasant taste.
● Can cause irritation to the mucous membranes.
● Requires patient compliance to keep the drug under the tongue until absorbed.
● Less suitable for sustained-release formulations.
4. Rectal Route
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller shikhapatel. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $10.00. You're not tied to anything after your purchase.
