Question

A neonate suffering from icterus is intravenously administered with phenobarbital. The justification for this therapy is:

• A. Phenobarbital is a short acting barbiturate and hence safe to induce sleep in neonates
• B. Phenobarbital suppresses the bilirubin synthesis in neonates
• C. Phenobarbital suppresses hepatic glucuronyl transferase and increases clearance of bilirubin
• D. Phenoarbital induces hepatic glucuronyl transferase and increases clearance of bilirubin

Answer 1

The Correct Option is D

The question is focused on the therapeutic use of phenobarbital in neonates suffering from icterus, which is a condition characterized by high levels of bilirubin in the blood, commonly referred to as jaundice.

Phenobarbital is a barbiturate that has various effects on the liver enzymes, particularly on neonatal jaundice treatment. The rationale behind its use can be explained as follows:

1. In cases of neonatal jaundice, the primary concern is the clearance of bilirubin from the body.
2. Phenobarbital is known to induce the enzyme hepatic glucuronyl transferase. This enzyme is crucial because it catalyzes the conjugation of bilirubin, making it water-soluble.
3. Once bilirubin is water-soluble, it can be excreted from the body more efficiently through the kidneys.

Considering the options:

• Option 1: "Phenobarbital is a short acting barbiturate and hence safe to induce sleep in neonates" is incorrect because the primary role of phenobarbital in this context is not to induce sleep, but to increase bilirubin clearance.
• Option 2: "Phenobarbital suppresses the bilirubin synthesis in neonates" is incorrect. Phenobarbital does not suppress bilirubin synthesis.
• Option 3: "Phenobarbital suppresses hepatic glucuronyl transferase and increases clearance of bilirubin" is incorrect. Phenobarbital induces, not suppresses, hepatic glucuronyl transferase.
• Option 4: "Phenobarbital induces hepatic glucuronyl transferase and increases clearance of bilirubin" is correct, explaining the therapeutic rationale behind its use.

Therefore, the correct answer is that phenobarbital induces hepatic glucuronyl transferase, which enhances the clearance of bilirubin, ultimately aiding in the management of neonatal jaundice.