Drug Administration via Oral Route

Oral Drug Administration

• Not all drugs can be administered orally; some forms that are not suitable for oral administration include gaseous, volatile, and unstable forms.

Drug Absorption

• Drug absorption typically begins in the small intestine for orally administered drugs.

First-Pass Effect

• The liver is the organ that chemically alters many drugs before they are transported via the bloodstream to their target site when taken orally.

Dosing and Route of Administration

• Some drugs are given in smaller doses when injected intravenously compared to when taken orally because the oral route involves first-pass effect, which reduces the amount of drug available for systemic circulation.

Food and Drug Interactions

• It is important for some drugs to be taken on an empty stomach because food can interfere with their absorption, reduce their efficacy, or increase the risk of side effects.
• Food and other drugs in the digestive tract can affect the absorption of orally administered drugs by altering their dissolution, solubility, and permeability.

Drug-Induced Ulcers

• Non-steroidal anti-inflammatory drugs (NSAIDs) can potentially cause or aggravate pre-existing ulcers due to their irritation of the digestive tract.

Drug Interactions

• One reason why some drugs should not be taken with certain other drugs is that they can interact with each other, resulting in reduced efficacy, increased side effects, or toxicity.

Limitations of Oral Route

• A common limitation of the oral route of drug administration is that it may not be suitable for drugs that are unstable or have low bioavailability, and alternative routes may be necessary.