Oral anti-parasitic drugs such as praziquantel are the treatment of choice. Treatment with praziquantel has been approved by the U.S. Food and Drug Administration and is quite effective against these parasites. Usual treatments are with praziquantel (5–10 mg/kg, single-administration) or niclosamide (adults and children over 6 years: 2 g, single-administration after a light breakfast, followed after 2 hours by a laxative; children aged 2–6 years: 1 g; children under 2 years: 500 mg). Albendazole is also highly effective. Atrabine is quite effective but has adverse effects in humans.

Tapeworms are treated with medications taken by mouth, usually in a single dose. The drug of choice for tapeworm infections is praziquantel. Niclosamide can also be used.

Upon diagnosis, treatment is quite simple and effective. The standard treatment for diphyllobothriasis, as well as many other tapeworm infections is a single dose of praziquantel, 5–10 mg/kg orally once for both adults and children. An alternative treatment is niclosamide, 2 g orally once for adults or 50 mg/kg (max 2 g) for children. Praziquantel is not FDA-approved for this indication and niclosamide is not available for human or even animal use in the United States. Reportedly, albendazole can also be effective. Another interesting potential diagnostic tool and treatment is the contrast medium, Gastrografin, introduced into the duodenum, which allows both visualization of the parasite, and has also been shown to cause detachment and passing of the whole worm.

The two drugs that have been well-described for the treatment of hymenolepiasis are praziquantel and niclosamide. Praziquantel, which is parasiticidal in a single dose for all the stages of the parasite, is the drug of choice because it acts very rapidly against "H. nana". Although structurally unrelated to other anthelminthics, it kills both adult worms and larvae. "In vitro", the drug produces vacuolization and disruption of the tegument in the neck of the worms, but not in more posterior portions of the strobila. Praziquantel is well absorbed when taken orally, and it undergoes first-pass metabolism and 80% of the dose is excreted as metabolites in urine within 24 hours.

Repeated treatment is required for "H. nana" at an interval of 7–10 days.

Praziquantel as a single dose (25 mg/kg) is the current treatment of choice for hymenolepiasis and has an efficacy of 96%. Single-dose albendazole (400 mg) is also very efficacious (>95%).

A three-day course of nitazoxanide is 75–93% efficacious. The dose is 1 g daily for adults and children over 12; 400 mg daily for children aged 4 to 11 years; and 200 mg daily for children aged 3 years or younger.

Cure rates are extremely good with modern treatments, but successful cure results may be of no symptomatic benefit to patients.

One treatment for sparganosis is praziquantel, administered at a dose of 120 to 150 mg/kg body weight over 2 days; however, praziquantel has had limited success. In general, infestation by one or a few sparganum larvae is often best treated by surgical removal.

DNA analysis of rare worms removed surgically can provide genome information to identify and characterise each parasite; treatments for the more common tapeworms can be cross-checked to see whether they are also likely to be effective against the species in question.

Asymptomatic cysts, such as those discovered incidentally on neuroimaging done for another reason, may never lead to symptomatic disease and in many cases do not require therapy. Calcified cysts have already died and involuted. Further antiparasitic therapy will be of no benefit.

Neurocysticercosis may present as hydrocephalus and acute onset seizures, thus the immediate therapy is emergent reduction of intracranial pressure and anticonvulsant medications. Once the seizures have been brought under control, antihelminthic treatments may be undertaken. The decision to treat with antiparasitic therapy is complex and based on the stage and number of cysts present, their location, and the persons specific symptoms.

Adult "Taenia solium" are easily treated with niclosamide, and is most commonly used in taeniasis. However cysticercosis is a complex disease and requires careful medication. Praziquantel (PZQ) is the drug of choice. In neurocysticercosis praziquantel is widely used. Albendazole appears to be more effective and a safe drug for neurocysticercosis. In complicated situation a combination of praziquantel, albendazole and steroid (such as corticosteroids to reduce the inflammation) is recommended. In the brain the cysts can be usually found on the surface. Most cases of brain cysts are found by accident, during diagnosis for other ailments. Surgical removals are the only option of complete removal even if treated successfully with medications.

Antiparasitic treatment should be given in combination with corticosteroids and anticonvulsants to reduce inflammation surrounding the cysts and lower the risk of seizures. When corticosteroids are given in combination with praziquantel, cimetidine is also given, as corticosteroids decrease action of praziquantel by enhancing its first pass metabolism. Albendazole is generally preferable over praziquantel due to its lower cost and fewer drug interactions.

Surgical intervention is much more likely to be needed in cases of intraventricular, racemose, or spinal neurocysticercosis. Treatments includes direct excision of ventricular cysts, shunting procedures, and removal of cysts via endoscopy.

In eye disease, surgical removal is necessary for cysts within the eye itself as treating intraocular lesions with anthelmintics will elicit an inflammatory reaction causing irreversible damage to structural components. Cysts outside the globe can be treated with anthelmintics and steroids. Treatment recommendations for subcutaneous cysticercosis includes surgery, praziquantel and albendazole.

Broad-spectrum benzimidazoles (such as albendazole and mebendazole) are the first line treatment of intestinal roundworm and tapeworm infections. Macrocyclic lactones (such as ivermectin) are effective against adult and migrating larval stages of nematodes. Praziquantel is the drug of choice for schistosomiasis, taeniasis, and most types of food-borne trematodiases. Oxamniquine is also widely used in mass deworming programmes. Pyrantel is commonly used for veterinary nematodiasis. Artemisinins and derivatives are proving to be candidates as drugs of choice for trematodiasis.

The disease is more complicated and severe when the oncospheres settle in the CNS tissue. This makes operating more difficult than when the disease presents in the muscles or subcutaneous tissues. The most common and widely recognized treatment for this disease is surgical removal of the cysts. However, this is not always possible. Other treatments that have seen positive results are Praziquantel and Albendazole. Praziquantel causes cell membranes of worms to become permeable. In this way the worm loses intracellular calcium. This in turn causes the worm to become paralyzed. Albendazole causes the worm to produce less ATP eventually leading to its death. Glucocorticoids can be used to help subdue the inflammatory symptoms of the disease.

For alveolar echinococcosis, surgical removal of cysts combined with chemotherapy (using albendazole and/or mebendazole) for up to two years after surgery is the only sure way to completely cure the disease. However, in inoperable cases, chemotherapy by itself can also be used. In treatment using just chemotherapy, one could use either mebendazole in three doses or albendazole in two doses. Since chemotherapy on its own is not guaranteed to completely rid the patient of disease, patients are often kept on the drugs for extended periods of times (i.e. more than 6 months, years). In addition to surgery and chemotherapy, liver transplants are being looked into as a form of treatment for alveolar echinococcosis although it is seen as incredibly risky since it often leads to echinococcosis re-infection in the patient afterwards.

For simple cases of cystic echinococcosis, the most common form of treatment is open surgical removal of the cysts combined with chemotherapy using albendazole and/or mebendazole before and after surgery. However, if there are cysts in multiple organs or tissues, or the cysts are in risky locations, surgery becomes impractical. For inoperable cases such as these, chemotherapy and/or PAIR (puncture-aspiration-injection-reaspiration) become alternative options of treatment. In the case of alternative treatment using just chemotherapy, albendazole is preferred twice a day for 1–5 months. An alternative to albendazole is mebendazole for at least 3 to 6 months. The other alternative to surgery is PAIR with chemotherapy. PAIR is a minimally invasive procedure that involves three steps: puncture and needle aspiration of the cyst, injection of a scolicidal solution for 20–30 min, and cyst-re-aspiration and final irrigation. Patients who undergo PAIR typically take albendazole or mebendazole from 7 days before the procedure until 28 days after the procedure. While open surgery still remains as the standard for cystic echinococcosis treatment, there have been a number of studies that suggest that PAIR with chemotherapy is more effective than surgery in terms of disease recurrence, and morbidity and mortality. In addition to the three above mentioned treatments, there is currently research and studies looking at new treatment involving percutaneous thermal ablation (PTA) of the germinal layer in the cyst by means of a radiofrequency ablation device. This form of treatment is still relatively new and requires much more testing before being widely used. An alternative to open surgery is laparoscopic surgery, which provides excellent cure rates with minimal morbidity and mortality.

The most common treatment for hookworm are benzimidazoles, specifically albendazole and mebendazole. BZAs kill adult worms by binding to the nematode’s β-tubulin and subsequently inhibiting microtubule polymerization within the parasite. In certain circumstances, levamisole and pyrantel pamoate may be used. A 2008 review found that the efficacy of single-dose treatments for hookworm infections were as follows: 72% for albendazole, 15% for mebendazole, and 31% for pyrantel pamoate. This substantiates prior claims that albendazole is much more effective than mebendazole for hookworm infections. Also of note is that the World Health Organization does recommend anthelmintic treatment in pregnant women after the first trimester. It is also recommended that if the patient also suffers from anemia that ferrous sulfate (200 mg) be administered three times daily at the same time as anthelmintic treatment; this should be continued until hemoglobin values return to normal which could take up to 3 months.

Hookworm infection can be treated with local cryotherapy when the hookworm is still in the skin.

Albendazole is effective both in the intestinal stage and during the stage the parasite is still migrating under the skin.

In case of anemia, iron supplementation can cause relief symptoms of iron deficiency anemia. However, as red blood cell levels are restored, shortage of other essentials such as folic acid or vitamin B12 may develop, so these might also be supplemented.

The fundamental prevention strategy is hygiene and sanitation. Secondary measures include stricter meat-inspection standards, livestock confinement, health education, safe meat preparation, mass drug therapy, and identifying and treating human and pig carriers. Moreover, a high level of sanitation and prevention of human faecal contamination of pig feeds also plays a major role in prevention. Infection can be prevented with proper disposal of human faeces around pigs, cooking meat thoroughly and/or freezing the meat at −10 °C for 5 days. For human cysticercosis, dirty hands are attributed to be the primary cause, and especially common among food handlers.

Proper cooking of meat is an effective prevention. For example, cooking (56 °C for 5 minutes) of beef viscera destroys cysticerci. Refrigeration, freezing (−10 °C for 9 days) or long periods of salting is also lethal to cysticerci. Inspection of beef and proper disposal of human excreta are also important measures.

Other important issues related to the treatment of hookworm are reinfection and drug resistance. It has been shown that reinfection after treatment can be extremely high. Some studies even show that 80% of pretreatment hookworm infection rates can be seen in treated communities within 30–36 months. While reinfection may occur, it is still recommended that regular treatments be conducted as it will minimize the occurrence of chronic outcomes. There are also increasing concerns about the issue of drug resistance. Drug resistance has appeared in front-line anthelmintics used for livestock nematodes. Generally human nematodes are less likely to develop resistance due to longer reproducing times, less frequent treatment, and more targeted treatment. Nonetheless, the global community must be careful to maintain the effectiveness of current anthelmintic as no new anthelmintic drugs are in the late-stage development.

Avoid ingestion of raw freshwater fish. Adequate cooking or freezing of freshwater fish will kill the encysted fish tapeworm larvae. Also, because human feces is an important mechanism for spreading eggs, proper disposal of sewage can cut down on infection of fish and thus of humans.

If complications of helminthiasis, such as intestinal obstruction occur, emergency surgery may be required. Patients who require non-emergency surgery, for instance for removal of worms from the biliary tree, can be pre-treated with the anthelmintic drug albendazole.

There is a lack of scientific study to support the efficacy of any particular treatment. An additional review published in 2009 made a similar conclusion, noting that because the diagnostics in use have been unreliable, it has been impossible to determine whether a drug has eradicated the infection, or just made the patient feel better. Historical reports, such as one from 1916, note difficulty associated with eradication of "Blastocystis" from patients, describing it as "an infection that is hard to get rid of."

A 1999 "in vitro" study from Pakistan found 40% of isolates are resistant to common antiprotozoal drugs. A study of isolates from patients diagnosed with IBS found 40% of isolates resistant to metronidazole and 32% resistant to furazolidone. Drugs reported in studies to be effective in eradicating "Blastocystis" infection have included metronidazole, trimethoprim, TMP-SMX (only trimethoprim is active with sulphamethoxazole demonstrating no activity), tetracycline, doxycycline, nitazoxanide, pentamidine, paromomycin and iodoquinol. Iodoquinol has been found to be less effective in practice than in-vitro. Miconazole and quinacrine have been reported as effective agents against "Blastocystis" growth in-vitro. Rifaximin, and albendazole have shown promise as has ivermectin which demonstrated high effectiveness against blastocystis hominis isolates in an in vitro study. There is also evidence that the probiotic yeast "Saccharomyces boulardii", and the plant mallotus oppositifolius may be effective against "Blastocystis" infections.

Physicians have described the successful use of a variety of discontinued antiprotozoals in treatment of "Blastocystis" infection. Emetine was reported as successful in cases in early 20th century with British soldiers who contracted "Blastocystis" infection while serving in Egypt. "In vitro" testing showed emetine was more effective than metronidazole or furazolidone. Emetine is available in the United States through special arrangement with the Center for Disease Control. Clioquinol (Entero-vioform) was noted as successful in treatment of "Blastocystis" infection but removed from the market following an adverse event in Japan. Stovarsol and Narsenol, two arsenic-based antiprotozoals, were reported to be effective against the infection. Carbarsone was available as an anti-infective compound in the United States as late as 1991, and was suggested as a possible treatment. The reduction in the availability of antiprotozoal drugs has been noted as a complicating factor in treatment of other protozoal infections. For example, in Australia, production of diloxanide furoate ended in 2003, paromomycin is available under special access provisions, and the availability of iodoquinol is limited.

The preventative measure of keeping cats inside in areas with high infection rates can prevent infection. Approved tick treatments for cats can be used but have been shown not to fully prevent tick bites.

The most often used treatments for cytauxzoonosis are imidocarb dipropionate and a combination of atovaquone and azithromycin. Although imidocarb has been used for years, it is not particularly effective. In a large study, only 25% of cats treated with this drug and supportive care survived. 60% of sick cats treated with supportive care and the combination of the anti-malarial drug atovaquone and the antibiotic azithromycin survived infection.

Quick referral to a veterinarian equipped to treat the disease may be beneficial. All infected cats require supportive care, including careful fluids, nutritional support, treatment for complications, and often blood transfusion.

Cats that survive the infection should be kept indoors as they can be persistent carriers after surviving infection and might indirectly infect other cats after being themselves bitten by a vector tick.

This disease has no vaccination.

Preventative measures can be taken at community and individual levels. Communities and governments can make sure their water supply remains sanitary and free of dog feces. Communities can control wild dog populations, thus preventing infection of the definitive host. Individuals should wash all fruits and vegetables thoroughly before eating and make sure their dogs are not infected with tapeworm.

Concomitant pinworm infection should also be excluded, although the association has not been proven. Successful treatment of the infection with iodoquinol, doxycycline, metronidazole, paromomycin, and secnidazole has been reported. Resistance requires the use of combination therapy to eradicate the organism. All persons living in the same residence should be screened for "D. fragilis", as asymptomatic carriers may provide a source of repeated infection. Paromomycin is an effective prophylactic for travellers who will encounter poor sanitation and unsafe drinking water.

Evidence in support of the idea that helminthic infections reduce the severity of autoimmune diseases is primarily derived from animal models. Studies conducted on mice and rat models of colitis, muscular sclerosis, type 1 diabetes, and asthma have shown helminth-infected subjects to display protection from the disease. While helminths are often considered a homogenous group, considerable differences exist between species and the utilization of species in clinical research varies between human and animal trials. As such, caution must be exercised when interpreting the results from animal models.

Helminthic therapy is currently being studied as a treatment for several (non-viral) autoimmune diseases in humans including celiac disease, Crohn's disease, multiple sclerosis, ulcerative colitis, and atherosclerosis. It is currently unknown which clinical dose or species of helminth is the most effective method of treatment. Hookworms have been linked to reduced risk of developing asthma, while "Ascaris lumbricoides" (roundworm infection) was associated with an "increased" risk of asthma. Similarly, "Hymenolepis nana", "Trichoris trichiura", "Ascaris lumbricoides", "Strongyloides stercolaris", "Enterobius vermicularis", and "Trichuris suis" ova have all been found to lower the number of symptom exacerbations, reduce the number of symptom relapses, and decrease the number of new or enlarging brain lesions in patients with multiple sclerosis at doses ranging from 1,180 to 9,340 eggs per gram. However, "Ascaris lumbricoides", "Strongyloides stercolaris" and "Enterobius vermicularis" are not considered suitable for therapeutic use in humans because they do not meet the criteria for a therapeutic helminth.

"Trichuris suis" ova has been used in most cases to treat autoimmune disorders because it is thought to be non-pathogenic in humans and therefore has been rendered as safe.

The use of "Trichuris suis" ova has been granted by the USA Food and Drug Administration as an investigational medicinal product (IMP). While in the UK, the hookworm "Necator americanus" has been granted an IMP license by the Medicines and Healthcare Regulatory Authority. This hookworm is likely to be relatively safe, although it can cause temporary gastrointestinal side effects, especially following the initial inoculation and with larger doses.

The general ideal characteristics for a therapeutic helminth are as follows:

- Little or no pathogenic potential

- Does not multiply in the host

- Cannot be directly spread to close contacts

- Produces a self-limited colonization in humans

- Produces an asymptomatic colonization in humans

- Does not alter behaviour in patients with depressed immunity

- Is not affected by most commonly used medications

- Can be eradicated with an anti-helminthic drug

- Can be isolated free of other potential pathogens

- Can be isolated or produced in large numbers

- Can be made stable for transport and storage

- Easy to administer

Most occurrences are found in areas that lack adequate sanitation and include Southeast Asia, West Africa, and East Africa.

Anecdotal data gathered from helminth self-treaters and their physicians and presented in socio-medical studies suggest that a much larger number of diseases may be amenable to helminthic therapy than are currently being investigated by formal clinical trials.

Because sparganosis is a rare infection, public health strategies have not made its prevention a priority. Public health strategies focusing on providing basic access to clean water may help to reduce future sparganosis infections. In their retrospective study of 25 cases of cerebral sparganosis, Song et al. found that 12 patients (48%) had eaten raw or uncooked frog or snake that was infected with sparganum, 5 patients (20%) had applied an animal's flesh as a poultice to an open wound, 4 patients had drunk contaminated water, and the cause of infection was not known for 4 patients. As a result of these findings, Song et al. conclude that health education about sparganosis and the importance of food sanitation should be implemented in all rural endemic areas. It has been recommended that water consumed in endemic areas should be boiled or treated to prevent ingestion of Cyclops or Spirometra larvae. Especially in areas where ponds or ditches provide potential habitats for infected copepods, public health strategies should include education campaigns about how to identify drinking water that could potentially be infected. Strategies should warn people against ingesting the raw flesh of the intermediate hosts, such as snakes and frogs, and against using them as poultices.