Antihelminthic drugs are medicines that rid the body of parasitic worms. People can become infected with parasitic worms in a number of ways. The eggs ofpinworms, for example, can be transferred from person to person through contaminated food, drinking glasses, clothing, or linens. Tapeworms and roundwormsmay enter the body when people eat undercooked meat or fish. The worms thenlive inside the body and may go unnoticed if they cause no troublesome symptoms. However, if they multiply rapidly or invade a vital organ, they can causeserious and sometimes life-threatening problems. The body has no natural means of getting rid of parasitic worms, but antihelminthic drugs do the job very well. Some kill the worms on contact. Others starve or paralyze the worms,which then pass out of the body in the feces.
Each type of antihelminthic drug is effective against particular kinds of worms. For example, niclosamide is effective against tapeworms, but will not work for treating pinworm or roundworm infections. Antihelminthic drugs are available only with a physician's prescription. They are sold as liquids and tablets (regular and chewable). Some commonly used antihelminthics are mebendazole (Vermox), niclosamide (Niclocide), praziquantel (Biltricide), pyrantel (Antiminth), and thiabendazole (Mintezol).
The proper dose depends on the patient, the type of antihelminthic drug, andthe condition for which it is being taken. The number of doses per day, the time between doses, and the length of treatment may also depend on these factors. To completely rid the body of parasitic worms, take the medicine exactlyas directed, for as long as directed. A second round of treatment a few weekslater may be necessary to make sure the infection is completely cleared.
Some antihelminthic medicines work best when taken with fatty foods, such aswhole milk or ice cream. Others should be taken after a light meal. Be sure to follow directions about when to take the medicine and what to take with it.People who cannot follow the directions because they are on low-fat or otherspecial diets should check with their physicians about how to take the medicine. Some people feel drowsy, dizzy, or less alert when using certain antihelminthic drugs. Anyone who takes these drugs should not drive, use machines ordo anything else that might be dangerous until they have found out how the drugs affect them.
Because some kinds of worms, such as pinworms, can be passed from one personto another, everyone in the household may need to take medicine when one person is infected. While under treatment with an antihelminthic drug, see the physician as often is recommended. The physician will check to see if the infection is clearing and will make sure no unwanted side effects exist. The physician may also suggest ways to help keep the infection from coming back. Be sure to follow these suggestions. Check with the physician if symptoms do not improve or if they get worse.
Patients being treated for hookworm or whipworm infections may need to take iron supplements. Ask the physician about this. People with certain medical conditions or who are taking certain other medicines can have problems if theytake antihelminthic drugs. Before taking these drugs, be sure to let the physician know about any of these conditions.Anyone who has had unusual reactionsto antihelminthic drugs in the past should let his or her physician know before taking the drugs again. The physician should also be told about any allergies to foods, dyes, preservatives, or other substances.
Women who are pregnant or who plan to become pregnant should check with theirphysicians before taking antihelminthic drugs. Some antihelminthic drugs pass into breast milk and may cause unwanted effects in nursing babies whose mothers take the medicine. Breastfeeding mothers who need to take antihelminthicdrugs should ask their physicians whether they need to stop breastfeeding.
Taking antihelminthic drugs with certain other drugs may affect the way the drugs work or may increase the chance of side effects. The most common side effects of antihelminthic drugs are dizziness, drowsiness, headache, sweating,dry mouth, dry eyes, and ringing or buzzing in the ears. These problems usually go away as the body adjusts to the drug and do not require medical treatment. Less common side effects of antihelminthic drugs, such as loss of appetite, diarrhea, nausea, vomiting, or stomach or abdominal pain or cramps, also may occur and do not need medical attention unless they do not go away or theyinterfere with normal activities. If more serious side effects are not common, but may occur. Call a physician immediately should any of unusual side effects occur. Antihelminthic drugs may interact with other medicines. When thishappens, the effects of one or both drugs may change, or the risk of side effects may be greater. Anyone who takes antihelminthic drugs should thereforetell the physician about all other medicines he or she is taking.