Human parasites depend on a host for nourishment, often to the detriment of the person infected. According to the U.S. Centers for Disease Control and Prevention, annually there are 7.4 million cases of parasitic infection caused by the protozoa, trichomonas, 2 million cases caused by the giardia protozoa and 1.5 million cases caused by toxoplasma protozoa. Treatments are available to rid the body of human parasites.
Albendazole
Albendazole is called an anthelmintic medication, which means that it is used in ridding the body of parasites. It stops both the larvae and the adult worms from using glucose, a form of sugar in the bloodstream. This results in the formation of less adenosine 5'-triphosphate, or ATP, which is the main form of energy for cells. With less ATP, the worms do not have the energy that their cells need to perform various functions; the final result is their immobilization. Albendazole also interferes with their cells being able to make microtubules, a substance they need to divide and multiply. According to the text "Basic & Clinical Pharmacology," albendazole is used to treat enterobius, trichuris, ascaris and toxicara, which are all roundworms. It can also be used to treat the tapeworm echinococcus.
Mebendazole
Mebendazole is also an anthelmintic medication, and can be used in the treatment of enterobius, trichuris, ascaris and necator roundworms. Like albendazole, it interferes with the ability of the parasite's cells to make microtubules, so their cells cannot divide and multiply.
Praziquantel
Alex Loukas, Ph.D., senior research fellow at the Queensland Institute of Medical Research, writes in "Goodman & Gilman's The Pharmacological Basis of Therapeutics" that the anthelmintic medication praziquantel makes the muscles of the parasites so active, that they eventually become paralyzed. When their muscles are paralyzed, they have to detach from the blood vessels and no longer have a source of nutrition. This medication is used against schistosomes, or flukes, and taenia, a genus of tapeworm.
Metronidazole
Metronidazole is an antiprotozoal medication. It is effective in the treatment of entamoeba, giardia and trichomonas, all protozoas. Margaret Phillips, Ph.D., professor of pharmacology at the University of Texas Southwestern Medical Center, explains in "Goodman & Gilman's The Pharmacological Basis of Therapeutics" that metronidazole is changed by the protozoa to an oxygen radical. This is a form of oxygen that is very toxic to the protozoan DNA. Their DNA is destroyed, which kills the protozoa.
Tetracycline
Tetracycline is an antibiotic; that is, it is used to treat specific bacterial infections. But it can also be used to kill some protozoa, because it enters the cells of the parasites and stops them from being able to make protein. Without protein, they cannot carry out the metabolic activities that they need to survive. Tetracycline is used to treat balantidium, a protozoan parasite.
Pyrimethamine and Sulfadiazine
This drug combination is used to treat toxoplasma gondii. Jeffrey Henderer, assistant professor of ophthalmology at the Thomas Jefferson University School of Medicine, writes in "Goodman & Gilman's The Pharmacological Basis of Therapeutics" that toxoplasma gondii is one of the most commonly seen protozoa in America. This parasite can even harm a fetus if the mother is infected and does not have the antibodies to fight against it. Pyrimethamine is an antiprotozoal medication, while sulfadiazine is an antimicrobial medication. The two work together to prevent toxoplasma from making folic acid. T. gondii must have folic acid to be able to grow.
References
- "Basic & Clinical Pharmacology"; Bertram Katzung, M.D., Ph.D., Susan Masters, Ph.D., Anthony Trevor, Ph.D.; 2009
- U.S. Centers for Disease Control and Prevention: About Parasites
- "Goodman & Gilman's The Pharmacological Basis of Therapeutics"; Laurence Brunton, Ph.D.; 2006
