Written by Rosemary Osuoha, B.Pharm
Last updated on june 12, 2025

Medically Reviewed By: Oladeji Robert B.Pharm, MPSN

Edited By: Ugwuleke Clement B.Pharm, MPSN

Antiparasitics are drugs or agents used to prevent, treat, or eliminate infections caused by parasites. Parasites are organisms that live on or inside another organism (the host) and benefit at the host’s expense. They include protozoa, helminths (worms), and ectoparasites (like lice or mites).

Diseases Caused by Protozoa

• Malaria — caused by Plasmodium species
  Drugs: Chloroquine, Artemisinin, Quinine, Mefloquine
• Amoebiasis — caused by Entamoeba histolytica
  Drugs: Metronidazole, Tinidazole
• Giardiasis — caused by Giardia lamblia
  Drugs: Metronidazole, Nitazoxanide
• Leishmaniasis — caused by Leishmania species
  Drugs: Amphotericin B, Miltefosine, Pentavalent antimonials
• Trypanosomiasis (Sleeping sickness) — caused by Trypanosoma brucei
  Drugs: Pentamidine, Suramin, Melarsoprol
• Trichomoniasis — caused by Trichomonas vaginalis
  Drugs: Metronidazole, Tinidazole

Diseases Caused by Helminths (Worms)

• Ascariasis — caused by Ascaris lumbricoides (roundworm)
  Drugs: Albendazole, Mebendazole
• Hookworm infection — caused by Ancylostoma duodenale and Necator americanus
  Drugs: Albendazole, Mebendazole
• Trichuriasis — caused by Trichuris trichiura (whipworm)
  Drugs: Albendazole, Mebendazole
• Strongyloidiasis — caused by Strongyloides stercoralis
  Drugs: Ivermectin
• Schistosomiasis — caused by Schistosoma species (blood flukes)
  Drugs: Praziquantel
• Taeniasis and Cysticercosis — caused by Taenia species (tapeworms)
  Drugs: Praziquantel, Niclosamide
• Filariasis — caused by Wuchereria bancrofti and other filarial worms
  Drugs: Diethylcarbamazine (DEC), Ivermectin

Diseases Caused by Ectoparasites

• Scabies — caused by Sarcoptes scabiei mite
  Drugs: Permethrin cream, Ivermectin
• Pediculosis (lice infestation)
  Drugs: Permethrin lotion, Malathion, Ivermectin

Common Antiparasitics Drugs

Major Classes of Antiparasitic Drugs

• Antiprotozoals
  Drugs targeting protozoan parasites like Plasmodium, Giardia, Entamoeba, and Trichomonas.
  Examples: Metronidazole, Chloroquine, Artemisinin, Pentamidine
• Anthelmintics
  Drugs that target helminths (worms), including nematodes (roundworms), cestodes (tapeworms), and trematodes (flukes).
  Examples: Albendazole, Mebendazole, Praziquantel, Ivermectin
• Ectoparasiticides
  Drugs used to kill or repel ectoparasites such as lice, mites, and ticks.
  Examples: Permethrin, Lindane, Ivermectin (topical)
• Antimalarials
  A specialized subset of antiprotozoals focused on treating malaria caused by Plasmodium species.
  Examples: Chloroquine, Artemisinin, Mefloquine, Quinine
• Antifilarials
  Drugs that target filarial worms causing diseases like lymphatic filariasis and onchocerciasis.
  Examples: Diethylcarbamazine (DEC), Ivermectin

If you're having a symptoms Call a Pharmacist

When Are Antiparasitics Used?

• Treatment of Active Infections: To eliminate parasites causing diseases such as malaria, amoebiasis, giardiasis, helminthiases, and ectoparasitic infestations.
• Prevention and Prophylaxis: In high-risk areas, antiparasitics may be used to prevent infections, e.g., antimalarials given to travelers or during malaria outbreaks.
• Mass Drug Administration (MDA): Used in endemic regions to control or eliminate parasitic diseases on a community-wide scale, such as filariasis or schistosomiasis.
• Control of Ectoparasites: To manage infestations like scabies and lice, especially in crowded or institutional settings.
• Before Surgical or Invasive Procedures: To reduce parasite load and prevent complications in some parasitic infections.
• Immunocompromised Patients: Special use in individuals with weakened immune systems who may have severe or atypical parasitic infections.

Limitations and Side Effects of Antiparasitics

• Drug Resistance: Overuse or misuse of antiparasitics can lead to resistant parasite strains, reducing treatment effectiveness.
• Toxicity and Side Effects: Some antiparasitics can cause adverse effects such as nausea, dizziness, allergic reactions, liver toxicity, or neurological symptoms.
• Limited Spectrum: Many antiparasitics target specific parasites, so accurate diagnosis is essential for effective treatment.
• Drug Interactions: Antiparasitic drugs can interact with other medications, affecting their efficacy or increasing side effects.
• Pregnancy and Lactation: Some antiparasitics are contraindicated or require caution during pregnancy and breastfeeding.
• Access and Cost: Availability and affordability of antiparasitic drugs can limit their use, especially in low-resource settings.