Recommended dose of BCG vaccine is?

NIA - 29 January 2023

Pharmacology

Easy

Appeared in: NIA - 29 January 2023

Explanation

The standard recommended dose of the BCG vaccine for children aged one month and older, and for adults, is 0.1 ml.
This dose is administered strictly via the intradermal route to ensure the formation of a characteristic wheal, which indicates correct placement within the skin layers.
While 0.1 ml is the standard dose, a reduced dose of 0.05 ml is specifically recommended for newborns (less than one month old) to minimize local adverse reactions.
The other options represent volumes that are too large for a standard intradermal injection and would be incorrect and unsafe.

Option B: A dose of 0.5 ml is five times the standard dose and is an excessively large volume for an intradermal injection. It would cause significant tissue irritation and a severe local reaction.
Option C: A dose of 1 ml is ten times the standard dose and is dangerously high for an intradermal injection. This volume is typically used for intramuscular injections.
Option D: A dose of 5 ml is fifty times the standard dose and is an extremely large volume for any standard injection, let alone an intradermal one. This would cause severe tissue damage.

Clinical Relevance

Nursing practice connection: Knowing BCG Vaccine Dosage and Administration helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
A key nursing responsibility is knowing the correct age-specific dose for BCG: 0.05 ml for neonates (<1 month) and 0.1 ml for all others. Administering the wrong dose can lead to complications or vaccine failure.
Correct intradermal technique is vital. If the vaccine is injected subcutaneously (too deep), it can cause a local abscess (cold abscess) and will not produce the protective scar, indicating that immunity may not have been conferred.
What if... a nurse accidentally administers the full 0.1 ml dose to a newborn instead of 0.05 ml? The nurse must document the error, inform the physician, and educate the parents to monitor for an exaggerated local reaction, such as a larger-than-normal ulcer or swollen lymph nodes in the armpit. The risk of suppurative lymphadenitis increases with the higher dose.

How to Approach the Question

First, identify the core of the question, which is the 'recommended dose' of the 'BCG vaccine'.
This is a factual recall question based on immunization schedules.
Recall that intradermal injections, like the BCG, involve very small volumes of fluid.
Evaluate the options. The doses 0.5 ml, 1 ml, and 5 ml are significantly large and more typical for intramuscular or subcutaneous routes, not intradermal.
This process of elimination leaves 0.1 ml as the only plausible answer for an intradermal vaccine.
For a complete understanding, also recall the special consideration for newborns, where the dose is halved to 0.05 ml, even though it's not an option here.

Concept Tested & Keywords

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