Drug Administration Routes, Preparation, and Administration

Core Concepts

Enteral routes: through the digestive tract

Enteral routes deliver a drug through the gastrointestinal tract. The most common is oral: the person swallows the dose. Oral dosing is convenient but subject to the first-pass effect — part of the dose is inactivated by the liver before reaching general circulation — and onset is slow. Sublingual (under the tongue) and buccal (against the cheek) routes absorb through the oral mucosa into the bloodstream, bypassing first pass, so they act faster with lower doses. Rectal administration avoids some first pass and helps when a person cannot take anything by mouth. Drugs may also be given through a feeding tube, with one critical rule: not every formulation may be crushed — extended-release and enteric-coated products release slowly or resist stomach acid, and altering them can dump the entire dose at once. Verify before crushing.

Parenteral routes: injected, bypassing the gut

Parenteral routes deliver drugs by injection, bypassing the digestive tract and, for most, avoiding first pass. Intravenous (IV) administration places the drug directly in the bloodstream: absorption is bypassed, onset is fastest, and control is precise — but the margin for error is smallest. Intramuscular (IM) injection deposits the drug in muscle, richly supplied with blood, so absorption is faster than subcutaneous but slower than IV. Subcutaneous (SC) injection places the drug in the fatty layer beneath the skin, where absorption is slower and more even. Intradermal (ID) injection delivers tiny volumes into the dermis, mainly for diagnostic testing. Because injections breach the skin, aseptic technique and proper site selection are essential — specifics vary by drug and facility policy, so they must be verified, not assumed.

Topical, transdermal, inhalation, and other routes

Topical application to the skin or mucous membranes is designed mostly for local effects. Transdermal patches are different: they deliver a drug steadily through the skin into the bloodstream over an extended period, producing relatively constant systemic levels — which is why old patches must be removed and disposed of properly when a new one is applied. Inhalation carries a drug into the lungs, where the large absorptive surface allows rapid onset — often for a local airway effect. Other routes include ophthalmic (eye), otic (ear), vaginal, and nasal administration. A drug intended for one route must never be given by another; route misuse is a serious, preventable error.

Preparation: turning the order into the right product

Preparation is where the order becomes reality. The nurse checks the order against the medication administration record (MAR), confirms the person's identity, and verifies the drug: correct drug, strength, form, expiration date, and calculation. Standard habits include reading the label three times (when the container is taken out, when the dose is prepared, and when it is returned), never preparing from an unlabeled container, and extra scrutiny for look-alike/sound-alike names and high-alert medications — classes carrying heightened risk of significant harm if misused (e.g., anticoagulants, insulin, opioids; verify the facility's list). Distractions during preparation are a known error contributor, which is why many facilities create quiet preparation zones.

The rights of medication administration

The rights of medication administration are a mnemonic checklist that organizes verification. Most versions include the right patient (confirmed with two identifiers, e.g., name and date of birth, per facility policy), right drug, right dose, right route, right time, and right documentation, with many sources adding right reason, right response, and the person's right to refuse. Versions vary by source and institution, so learn the one your program and facility use. The rights structure double-checking but do not replace judgment: the nurse still applies knowledge of the drug, the person's condition, and assessment findings before, during, and after administration.

Administration and follow-up

Administration follows a sequence: assess the person first (allergies, condition, and any relevant vital signs or labs per the drug's requirements), verify the rights, give the drug, observe for response and adverse effects, document promptly, and teach the person what to expect. A person always has the right to refuse; the nurse respects the refusal, explores the reason, notifies the prescriber, and documents. Nurses work within their license and facility policy; delegation of medication tasks — where permitted — is strictly limited by law. When anything is uncertain — an unclear order, an unfamiliar product, a questionable calculation — stop and verify.

Common Confusions