CMT Medication Administration Routes 2 — Questions and Answers
Question 1: The sublingual route of medication administration involves placing the medication:
- Under the tongue (Correct answer)
- Between the cheek and gum
- In the ear canal
- On the skin surface
Correct answer: Under the tongue
Sublingual means 'under the tongue,' where the medication dissolves and is absorbed directly into the bloodstream through the oral mucosa.
Sublingual administration provides rapid drug absorption through the highly vascular mucosa under the tongue, bypassing first-pass metabolism in the liver. This results in faster onset and higher bioavailability compared to oral (swallowed) medications. The most common sublingual medication is nitroglycerin for angina relief. Patients should not eat, drink, or smoke during sublingual administration. The medication should be placed under the tongue and allowed to dissolve completely without swallowing. Buccal administration (between cheek and gum) is similar but uses a different mucosal surface.
Question 2: Which injection route has the slowest absorption rate?
- Intravenous
- Intramuscular
- Subcutaneous
- Intradermal (Correct answer)
Correct answer: Intradermal
Intradermal injections are placed in the dermis, which has limited blood supply, resulting in the slowest absorption.
Absorption rates from fastest to slowest: intravenous (immediate—directly into bloodstream), intramuscular (moderate—well-vascularized muscle tissue absorbs within 10-20 minutes), subcutaneous (slower—fat tissue has less blood supply, absorption takes 15-30 minutes or longer), intradermal (slowest—the dermis has very limited vascularity). Intradermal injections (TB skin test, allergy testing) use a 25-27 gauge needle at a 5-15 degree angle, injecting only 0.01-0.1 mL into the dermis to create a visible wheal. The slow absorption is actually desired for these diagnostic tests.
Question 3: Transdermal medication patches work by:
- Injecting medication through the skin with microneedles
- Delivering medication through intact skin into systemic circulation over time (Correct answer)
- Numbing only the skin surface
- Absorbing toxins from the skin
Correct answer: Delivering medication through intact skin into systemic circulation over time
Transdermal patches deliver medication through the intact skin at a controlled rate for systemic absorption over hours or days.
Transdermal drug delivery systems release medication at a controlled rate through the skin into the capillary network for systemic circulation. Advantages include sustained drug levels, avoidance of first-pass metabolism, improved compliance, and non-invasive application. Common transdermal medications include fentanyl (pain), nitroglycerin (angina), nicotine (smoking cessation), estrogen (hormone replacement), and scopolamine (motion sickness). Application rules: rotate sites to prevent skin irritation, apply to clean, dry, hairless skin (do not shave—clip if needed), avoid areas with cuts or irritation, date and initial the patch, and remove the old patch before applying a new one.
Question 4: When administering eye drops, the medication should be instilled into the:
- Center of the cornea
- Upper eyelid
- Lower conjunctival sac (Correct answer)
- Inner canthus
Correct answer: Lower conjunctival sac
Eye drops are placed into the lower conjunctival sac (the pocket formed by gently pulling down the lower eyelid) to avoid direct corneal irritation.
Proper ophthalmic instillation technique: (1) Perform hand hygiene and don gloves, (2) Have patient look up, (3) Gently pull down the lower eyelid to expose the conjunctival sac, (4) Instill the prescribed number of drops into the conjunctival sac (not directly on the cornea), (5) Release the lid and have patient close eyes gently (not squeezing), (6) Apply gentle pressure to the nasolacrimal duct (inner corner of eye) for 1-2 minutes to prevent systemic absorption, (7) Wait 5 minutes between different eye medications. Never touch the dropper tip to the eye or any surface. For ointments, apply a thin ribbon along the inner lower lid from inner to outer canthus.
Question 5: The intravenous (IV) route is preferred in emergencies because:
- It is the easiest to administer
- It provides immediate drug bioavailability and rapid onset (Correct answer)
- It requires the smallest needle
- It causes the least pain
Correct answer: It provides immediate drug bioavailability and rapid onset
IV administration delivers medication directly into the bloodstream, providing 100% bioavailability and immediate onset of action.
Intravenous administration provides the fastest onset because medication enters the systemic circulation immediately without requiring absorption. Bioavailability is 100%—the entire dose reaches the bloodstream. In emergencies, this allows rapid titration of critical medications (epinephrine, atropine, vasopressors). IV medications can be given as bolus (push—rapid injection), intermittent infusion (over 15-60 minutes), or continuous infusion (ongoing drip). Disadvantages include infection risk, phlebitis, infiltration, air embolism, and the inability to recall medication once administered. Medical technicians must verify IV competency is within their scope of practice.
Question 6: Rectal medication administration is appropriate when a patient:
- Has an IV line available
- Is vomiting and unable to take oral medications (Correct answer)
- Prefers this route over oral
- Has a rectal infection
Correct answer: Is vomiting and unable to take oral medications
The rectal route is used when oral administration is not possible due to nausea, vomiting, unconsciousness, or NPO status.
Rectal administration is indicated when oral intake is impossible (vomiting, seizures, unconsciousness, NPO), when drugs would be destroyed by gastric acid, or for local effects (hemorrhoids, constipation). Medications include suppositories and enemas. Approximately 50% of rectally absorbed medication bypasses first-pass hepatic metabolism (through the inferior and middle rectal veins). Administration technique: position patient in left lateral (Sims') position, lubricate suppository, insert past the internal anal sphincter (approximately 1 inch in adults), and have patient remain lying down for 15-20 minutes. Contraindications include rectal surgery, active bleeding, and low platelet counts.
CMT Medication Administration Routes 2
The sublingual route of medication administration involves placing the medication: