Antiparasitic drugs: All You Should Know

If you have ever been curious about parasitic medications, this article is for you. We will discuss the different types of parasitic medications, their uses, and their side effects.

What are antiparasitic drugs?

Antiparasitic meds work by killing or inhibiting the growth of parasites. Some parasites cause disease, while others do not. Some common symptoms include itching, rash, and abdominal pain.

What do antiparasitic drugs treat?

The 3 types of parasites that usually infect humans: ectoparasites, helminths, and protozoa. – Ectoparasites are parasites that live on the skin, e.g ticks, lice, and fleas. They can cause skin irritation and sometimes transmit diseases. – Helminths are parasitic worms that reside inside the body. They can cause a variety of problems, including intestinal blockages and malnutrition. – Protozoa are single-celled parasites that cause malaria, cholera, etc.

Common Parasitic Infections in the USA

The most frequently documented parasitic infections in the USA include:

  1. Giardiasis: Symptoms of giardiasis include diarrhea, bloating, and weight loss.
  2. Cryptosporidiosis: This is an infection of the gastrointestinal tract that is caused by Cryptosporidium parvum. Symptoms of cryptosporidiosis include watery diarrhea, nausea, and vomiting.
  3. Trichomoniasis: This is an infection of the genital tract caused by Trichomonas vaginalis. Symptoms of trichomoniasis include vaginal discharge, itching, and burning during urination.
  4. Cyclosporiasis: This is an infection of the gastrointestinal tract caused by Cyclospora cayetanensis. Symptoms of cyclosporiasis include watery diarrhea, bloating, fatigue, and weight loss.
  5. Amebiasis: Is associated with Entamoeba histolytica. Symptoms of amebiasis include diarrhea and blood in the stool.

How do antiparasitic drugs work?

The vast majority of these drugs function by interfering with the parasites’ life cycle in some way. For example, they may prevent the parasite from maturing or reproducing, or they may kill the parasite outright.

Some antiparasitic drugs are designed to work against specific types of parasites, while others are great at killing a wide range of different ones. Below, we will discuss the most common ones.

Metronidazole and Tinidazole

Two commonly used antiparasitic drugs are metronidazole and tinidazole. Metronidazole is effective against Giardia lamblia, Trichomonas vaginalis, and Entamoeba histolytica infections. Tinidazole is effective against infections listed above as well as Helicobacter pylori. Metronidazole and tinidazole are generally well tolerated. Common adverse effects include nausea, diarrhea, abdominal pain, and vomiting. Some people may also experience headache, dizziness, or rash. Serious side effects are rare but can include severe allergic reactions, liver damage, and nerve problems.


Ivermectin is a medication used to treat a number of parasitic worm infections. This includes head lice, onchocerciasis, trichuriasis, ascariasis, strongyloidiasis, and lymphatic filariasis. Ivermectin is also effective against other parasitic infections such as demodex mites and ear mites.


Albendazole is a medication used to treat a variety of parasitic worm infestations. This includes ascariasis, pinworm disease, hookworm infections, guinea worm disease, and strongyloidiasis. It is taken by mouth as a single dose. Side effects include bloating, vomiting, headache, rash, and dizziness. Albendazole should not be used in pregnancy unless the benefit outweighs the risk. It is in the benzimidazole class of medications and works by causing the death of the worm.

You might also like: