Protamine sulphate is the antidote for?

Appeared in: RUHS, Jaipur, M.Sc Nursing Entrance Exam-2021

Explanation

Protamine sulphate is the specific pharmacological antidote for heparin.
It functions by chemically neutralizing heparin. As a strongly basic (cationic) protein, it binds with the strongly acidic (anionic) heparin molecule.
This binding forms a stable and inactive salt complex, which immediately reverses the anticoagulant effects of heparin.
The standard dosage is 1 mg of protamine for every 100 units of heparin that needs to be reversed.

Option B: Morphine is an opioid analgesic. The antidote for morphine and other opioid overdoses is Naloxone.
Option C: Warfarin is an oral anticoagulant. Its effects are reversed by administering Vitamin K (phytonadione).
Option D: Cyanide is a highly toxic chemical poison. Its antidotes include hydroxocobalamin or a kit containing amyl nitrite, sodium nitrite, and sodium thiosulfate.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Pharmacology: Antidotes for Drug Overdose as background academic context rather than a clinical decision trigger.
Knowledge of antidotes is a critical patient safety competency for nurses, especially in emergency departments, intensive care units, and operating rooms where potent drugs like heparin are frequently used.
Prompt recognition of heparin overdose (e.g., spontaneous bleeding, hematuria, rapidly dropping hemoglobin) and preparation for protamine administration can prevent life-threatening hemorrhage.
Nurses must be aware of potential adverse reactions to protamine, including hypotension and anaphylaxis, particularly in patients with fish allergies or prior exposure (e.g., NPH insulin, vasectomy).

How to Approach the Question

This is a direct recall question testing knowledge of pharmacology.
First, identify the drug mentioned in the question stem: 'Protamine sulphate'.
Recall the primary function of this drug. Protamine sulphate is known as a reversal agent or antidote.
Next, analyze the options provided, which are all drugs or toxins.
Systematically evaluate each option to determine which one is neutralized by protamine sulphate.
Recall that heparin is an anticoagulant whose action is reversed by protamine sulphate. This makes it the correct answer.

Concept Tested & Keywords

Q92U_fs_1cjb0UwwLqZII5

E6 Pharmacology Nursing Lilley 11e Part 2 pp. 108-110, 123-125

E6 Pharmacology Katzung 16e p. 958-960

Practise the full RUHS, Jaipur, M.Sc Nursing Entrance Exam-2021

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