Mr. Kishan is on Thyroxine 100 mg daily. The nurse instructs the patient to take the medicine daily?

Appeared in: SCTIMST Staff Nurse - 2015 (Set-B)

Explanation

Levothyroxine, the synthetic form of thyroxine (T4), must be taken on an empty stomach to ensure consistent and optimal absorption.
The standard instruction is to take the tablet with a full glass of water 30 to 60 minutes before the first meal of the day (breakfast).
Food, coffee, and certain medications can significantly interfere with its absorption, leading to sub-therapeutic levels and poor control of hypothyroidism.

Option A: Taking levothyroxine with food significantly reduces its absorption from the gastrointestinal tract.
Option B: Taking the medication half an hour after food means the stomach is not empty, which will impair drug absorption.
Option D: Milk contains calcium, which binds to levothyroxine and prevents its absorption. This would make the medication ineffective.

Clinical Relevance

Nursing practice connection: Use the key finding related to Pharmacology: Safe Administration of Levothyroxine to guide bedside assessment, documentation, and the next nursing action.
A primary nursing responsibility is patient education, especially for chronic medications like levothyroxine, to ensure therapeutic efficacy and prevent complications.
Nurses are the last line of defense against medication errors. It is critical to verify any prescription that seems incorrect. A dose of '100 mg' for thyroxine is a 'never' event and must be questioned immediately with the prescriber.
What if the patient is on tube feeding? Tube feedings, especially soy-based formulas, can impair levothyroxine absorption. The feeding should be stopped for at least one hour before and one hour after medication administration.

How to Approach the Question

First, identify the drug in the question: Thyroxine (levothyroxine).
Second, perform a safety check on the prescription details. The dose is '100 mg'. Immediately recognize that this is an extreme deviation from the standard dosage unit (mcg) and represents a critical safety risk.
Third, recall the fundamental administration rule for this drug. Levothyroxine requires an empty stomach for proper absorption.
Fourth, evaluate each option against this rule:
Option A (with food) and B (after food) violate the 'empty stomach' rule.
Option D (with milk) introduces calcium, a known substance that interferes with absorption.

Concept Tested & Keywords

Concept Tested: Pharmacology: Safe Administration of Levothyroxine
Stem keywords: Thyroxine, 100 mg, instructs, take the medicine
Lead-in keywords: instructs
Clinical cues: The dose of '100 mg' is a major clinical cue for a potential medication error, as thyroxine is dosed in mcg.

Q3z37FzgLxjs8OQKDhRD40

E6 Pharmacology Nursing Lilley 11e Part 2 p. 186-188

E6 Pharmacology Katzung 16e p. 1086-1088

E6 Medicine Harrison 22e Part 2 p. 935-937

Practise the full SCTIMST Staff Nurse - 2015 (Set-B)

Attempt every question from this paper in a timed mock, then review the full solution for each one.