A patient presented with diarrhea and his stool examination showed the egg for H. Nana. What is drug of choice?
**Core Concept**
The patient's symptoms of diarrhea and the presence of H. nana eggs in the stool indicate a diagnosis of Hymenolepiasis, a type of intestinal tapeworm infection caused by the parasite Hymenolepis nana. The drug of choice for treating this infection is a anthelmintic agent that can effectively kill the parasite.
**Why the Correct Answer is Right**
The anthelmintic drug praziquantel is the drug of choice for treating Hymenolepiasis. Praziquantel works by causing the death of the parasite by interfering with its nerve function, ultimately leading to paralysis and expulsion of the parasite from the body. This is achieved through the inhibition of nicotinic acetylcholine receptors on the muscle cells of the parasite, which results in muscle contraction and eventual death.
**Why Each Wrong Option is Incorrect**
* **Option A:** Albendazole is an anthelmintic agent used to treat various parasitic worm infections, but it is not the first-line treatment for Hymenolepiasis. It may be used in certain cases where praziquantel is not available or effective.
* **Option B:** Mebendazole is another anthelmintic agent that is effective against certain parasitic worm infections, but it is not the preferred treatment for Hymenolepiasis.
* **Option C:** Pyrantel is an anthelmintic agent that is used to treat infections caused by certain types of roundworms, but it is not effective against Hymenolepiasis.
**Clinical Pearl / High-Yield Fact**
It is essential to note that praziquantel can cause side effects such as abdominal pain, nausea, and diarrhea, especially in large doses. However, the benefits of treatment usually outweigh the risks, and the drug is generally well-tolerated.
**Correct Answer:** C. Praziquantel.