Drug administration route

In pharmacology and medicine, drug administration routes are "the various ways of administering a drug or other chemical to a site in a patient or animal from where the chemical is absorbed into the blood and delivered to the target tissue."

Examples include:

• oral drug administration
• transmucosal drug administration
• transdermal drug administration
  • iontophoresis
• nasal inhalation
• intratracheal inhalation
• opthalmic drug administration
• intradermal injection
• subcutaneous injection
  • hypodermoclysis
• intravenous injection
  • intravenous bolus
  • intravenous infusion
• intraosseous infusion
• intra-articular injection

There are many reasons, including clinical, cultural, and cost factors for selecting a route of administration. Oral administration is usually cheapest and most convenient in adult humans, but many drugs are destroyed by the gastrointestinal tract. It can also be quite difficult to administer oral drugs to a child or an animal. People in both advanced and less developed countries may not follow an oral regimen over time, but take all the pills at once, thinking "if one is good, more is better."

Considerable skill may be needed to use some of the parenteral routes. The infusion techniques need to be protected to avoid iatrogenic infections.