**Core Concept**
Pityriasis rosea-like drug eruptions are a type of skin reaction that resembles the clinical presentation of pityriasis rosea, a viral exanthem. These eruptions are often caused by medications that trigger an immune-mediated response, leading to the formation of skin lesions.

**Why the Correct Answer is Right**
The correct answer is linked to the mechanism of drug-induced skin reactions, which involve the activation of T-cells and the release of cytokines. In the case of pityriasis rosea-like drug eruptions, the medication triggers an immune response that results in the formation of characteristic skin lesions, including herald patches and secondary lesions. This reaction is often associated with medications that are metabolized by the cytochrome P450 enzyme system, particularly those that induce the CYP3A4 enzyme.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately describe a medication commonly associated with pityriasis rosea-like drug eruptions. While some anticonvulsants can cause skin reactions, they are not typically associated with this specific type of eruption.

**Option B:** This option is incorrect because it is not a medication that is commonly linked to pityriasis rosea-like drug eruptions. Although some antibiotics can cause skin reactions, they are not typically associated with this specific type of eruption.

**Option C:** This option is correct because beta-lactam antibiotics, particularly amoxicillin and ampicillin, are known to cause pityriasis rosea-like drug eruptions in some individuals.

**Option D:** This option is incorrect because it does not accurately describe a medication commonly associated with pityriasis rosea-like drug eruptions. While some antihistamines can cause skin reactions, they are not typically associated with this specific type of eruption.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that drug-induced skin reactions can resemble viral exanthems, such as pityriasis rosea. When evaluating a patient with a skin eruption, it's crucial to consider the medication history and the timing of the eruption in relation to the initiation of the medication.

**Correct Answer:** C.