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There is no consensus on optimal therapeutic approach. The most commonly used drug is diethylcarbamazine (DEC), but it is, however, often ineffective. Although other drugs have been tried such as praziquantel, ivermectin, and albendozole, none has proven to be reliably and rapidly effective. Mebendazole appeared more active than DEC in eliminating the infection, and had comparable overall responses. Thiabendazole evidenced a small, but significant activity against the infection. A combination of treatments, DEC plus mebendazole, was much more effective than single drug doses.
Prevention can be partially achieved through limiting contact with vectors through the use of DEET and other repellents, but due to the predominantly relatively mild symptoms and the infection being generally asymptomatic, little has formally been done to control the disease.
The drug of choice for the treatment of uncomplicated strongyloidiasis is ivermectin. Ivermectin does not kill the "Strongyloides" larvae, only the adult worms, therefore repeat dosing may be necessary to properly eradicate the infection. There is an auto-infective cycle of roughly two weeks in which Ivermectin should be re-administered however additional dosing may still be necessary as it will not kill "Strongyloides" in the blood or larvae deep within the bowels or diverticula. Other drugs that are effective are albendazole and thiabendazole (25 mg/kg twice daily for 5 days—400 mg maximum (generally)). All patients who are at risk of disseminated strongyloidiasis should be treated. The optimal duration of treatment for patients with disseminated infections is not clear.
Treatment of strongyloidiasis can be difficult and "Strongyloides" has been known to live in individuals for decades; even after treatment. Continued treatment is thus necessary even if symptoms resolve.
Because of the high cost of Stromectol, the veterinary formula Ivomec can be used. Government programs are needed to help citizens finance lifelong medication.
Clothes and sheets must be washed with enzyme washing powder and dried on hot daily.
Antifungal drugs are used to treat mycoses. Depending on the nature of the infection, a topical or systemic agent may be used.
Example of antifungals include: fluconazole which is the basis of many over-the-counter antifungal treatments. Another example is amphotericin B which is more potent and used in the treatment of the most severe fungal infections that show resistance to other forms of treatment and it is administered intravenously.
Drugs to treat skin infections are the azoles: ketoconazole, itraconazole, terbinafine among others.
Yeast infections in the vagina, caused by "Candida albicans", can be treated with medicated suppositories such as tioconazole and pessaries whereas skin yeast infections are treated with medicated ointments.
Parasitic infections can usually be treated with antiparasitic drugs.
Albendazole and mebendazole have been the treatments administered to entire populations to control hookworm infection. However, it is a costly option and both children and adults become reinfected within a few months after deparasitation occurs raising concerns because the treatment has to repeatedly be administered and drug resistance may occur.
Another medication administered to kill worm infections has been pyrantel pamoate. For some parasitic diseases, there is no treatment and, in the case of serious symptoms, medication intended to kill the parasite is administered, whereas, in other cases, symptom relief options are used. Recent papers have also proposed the use of viruses to treat infections caused by protozoa.
Anti-helminthics are often used to kill off the worms, however in some cases this may cause patients to worsen due to toxins released by the dying worms. Albendazole, ivermectin, mebendazole, and pyrantel are all commonly used, though albendazole is usually the drug of choice. Studies have shown that anti-helminthic drugs may shorten the course of the disease and relieve symptoms. Therefore anti-helminthics are generally recommended, but should be administered gradually so as to limit the inflammatory reaction.
Medication is the primary treatment for pinworm infection. They are so effective that many medical scientists regard hygienic measures as impractical. However, reinfection is frequent regardless of the medication used. Total elimination of the parasite in a household may require repeated doses of medication for up to a year or more. Because the drugs kill the adult pinworms, but not the eggs, the first retreatment is recommended in two weeks. Also, if one household member spreads the eggs to another, it will be a matter of two or three weeks before those eggs become adult worms and thus amenable to treatment. Asymptomatic infections, often in small children, can serve as reservoirs of infection, and therefore the entire household should be treated regardless of whether or not symptoms are present.
The benzimidazole compounds albendazole (brand names e.g., "Albenza", "Eskazole", "Zentel" and "Andazol") and mebendazole (brand names e.g., "Ovex", "Vermox", "Antiox" and "Pripsen") are the most effective. They work by inhibiting the microtubule function in the pinworm adults, causing glycogen depletion, thereby effectively starving the parasite. A single 100 milligram dose of mebendazole with one repetition after a week, is considered the safest, and is usually effective with cure rate of 96%. Mebendazole has no serious side effects, although abdominal pain and diarrhea have been reported. Pyrantel pamoate (also called pyrantel embonate, brand names e.g., "Reese's Pinworm Medicine", "Pin-X", "Combantrin", "Anthel", "Helmintox", and "Helmex") kills adult pinworms through neuromuscular blockade, and is considered as effective as the benzimidazole compounds and is used as a second-line medication. Other medications are piperazine, which causes flaccid paralysis in the adult pinworms, and pyrvinium pamoate (also called pyrvinium embonate), which works by inhibiting oxygen uptake of the adult pinworms. Pinworms located in the genitourinary system (in this case, female genital area) may require other drug treatments.
The drug of choice for the treatment of hookworm disease is mebendazole which
is effective against both species, and in addition, will remove the intestinal
worm Ascaris also, if present. The drug is very efficient, requiring only a
single dose and is inexpensive. However, treatment requires
more than giving the anthelmintic, the patient should also receive dietary
supplements to improve their general level of health, in particular iron
supplementation is very important. Iron is an important constituent of a
multitude of enzyme systems involved in energy metabolism, DNA synthesis and
drug detoxification.
An infection of "N. americanus" parasites can be treated by using benzimidazoles, albendazole, and mebendazole. A blood transfusion may be necessary in severe cases of anemia. Light infections are usually left untreated in areas where reinfection is common. Iron supplements and a diet high in protein will speed the recovery process. In a case study involving 56–60 men with "Trichuris trichiura" and/or "N. americanus" infections, both albendazole and mebendazole were 90% effective in curing "T. trichiura". However, albendazole had a 95% cure rate for "N. americanus", while mebendazole only had a 21% cure rate. This suggests albendazole is most effective for treating both "T. trichiura" and "N. americanus".
Currently, no therapeutic drugs are prescribed for the disease. Therefore, prevention is the sole mode of treatment. This disease can only be prevented by quarantining sick birds and preventing migration of birds around the house, causing them to spread the disease. Deworming of birds with anthelmintics can reduce exposure to the cecal nematodes that carry the protozoan. Good management of the farm, including immediate quarantine of infected birds and sanitation, is the main useful strategy for controlling the spread of the parasitic contamination. The only drug used for the control (prophylaxis) in the United States is nitarsone at 0.01875% of feed until 5 days before marketing. Natustat and nitarsone were shown to be effective therapeutic drugs. Nifurtimox, a compound with known antiprotozoal activity, was demonstrated to be significantly effective at 300–400 ppm, and well tolerated by turkeys.
Keeping the skin clean and dry, as well as maintaining good hygiene, will help larger topical mycoses. Because fungal infections are contagious, it is important to wash after touching other people or animals. Sports clothing should also be washed after use.
Anti-helminthics should generally be paired with corticosteroids in severe infections to limit the inflammatory reaction to the dying parasites. Studies suggest that a two-week regimen of a combination of mebendazole and prednisolone significantly shortened the course of the disease and length of associated headaches without observed harmful side effects. Other studies suggest that albendazole may be more favorable, because it may be less like to incite an inflammatory reaction. The Chinese herbal medicine long-dan-xie-gan-tan (LDGXT) has also been shown to have a similar anti inflammatory effect, and in mild cases may be used alone to relieve symptoms while infection resolves itself.
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.
Treatment of loiasis involves chemotherapy or, in some cases, surgical removal of adult worms followed by systemic treatment. The current drug of choice for therapy is diethylcarbamazine (DEC), though ivermectin use is not unwarranted. The recommend dosage of DEC is 6 mg/kg/d taken three times daily for 12 days. The pediatric dose is the same. DEC is effective against microfilariae and somewhat effective against macrofilariae (adult worms).
In patients with high microfilaria load, however, treatment with DEC may be contraindicated, as the rapid microfilaricidal actions of the drug can provoke encephalopathy. In these cases, albendazole administration has proved helpful, and superior to ivermectin, which can also be risky despite its slower-acting microfilaricidal effects.
Management of "Loa loa" infection in some instances can involve surgery, though the timeframe during which surgical removal of the worm must be carried out is very short. A detailed surgical strategy to remove an adult worm is as follows (from a real case in New York City). The 2007 procedure to remove an adult worm from a male Gabonian immigrant employed proparacaine and povidone-iodine drops, a wire eyelid speculum, and 0.5 ml 2% lidocaine with epinephrine 1:100,000, injected superiorly. A 2-mm incision was made and the immobile worm was removed with forceps. Gatifloxacin drops and an eye-patch over ointment were utilized post surgery and there were no complications (unfortunately, the patient did not return for DEC therapy to manage the additional worm—and microfilariae—present in his body).
An infection of "N. americanus" parasites can be treated by using benzimidazoles: albendazole or mebendazole. A blood transfusion may be necessary in severe cases of anemia. Light infections are usually left untreated in areas where reinfection is common. Iron supplements and a diet high in protein will speed the recovery process. In a case study involving 56-60 men with "Trichuris trichiura" and/or "N. americanus" infections, both albendazole and mebendazole were 90% effective in curing "T. trichiura". However, albendazole had a 95% cure rate for "N. americanus", while mebendazole only had a 21% cure rate. This suggests albendazole is most effective for treating both "T. trichiura" and "N. americanus".
Cryotherapy by application of liquid nitrogen to the skin has been used to kill cutaneous larvae migrans, but the procedure has a low cure rate and a high incidence of pain and severe skin damage, so it now is passed over in favor of suitable pharmaceuticals. Topical application of some pharmaceuticals has merit, but requires repeated, persistent applications and is less effective than some systemic treatments.
One strategy to control the disease in areas where it is common is the treatment of entire groups of people regardless of symptoms via mass drug administration. This is often done among school-age children and is known as deworming. While testing and treating children who are infected looks like it is effective, there is insufficient evidence to conclude that routine deworming, in the absence of a positive test, improves nutrition, haemoglobin, school attendance or school performance.
For this purpose, broad-spectrum benzimidazoles such as mebendazole and albendazole are the drugs of choice recommended by WHO. These anthelminthics are administered in a single dose are safe, relatively inexpensive, and effective for several months. Mebendazole can be given with a single dose twice a day for three consecutive days. Albendazole is given at a single dose. WHO recommends annual treatment in areas where between 20 and 50% of people are infected, and a twice a year treatment if it is over 50%; and in low risk situation (i.e. less than 20% prevalence) case-by-case treatment. In addition to these, pyrantel pamoate is also equally effective on ascaris. However, it has been reported that albendazole, mebendazole, and pyrantel pamoate are not entirely effective against "T. trichiura" with single oral doses in population-based control.
Several drugs are effective for fascioliasis, both in humans and in domestic animals. The drug of choice in the treatment of fasciolosis is triclabendazole, a member of the benzimidazole family of anthelmintics. The drug works by preventing the polymerization of the molecule tubulin into the cytoskeletal structures, microtubules. Resistance of "F. hepatica" to triclabendazole has been recorded in Australia in 1995 and Ireland in 1998.
Praziquantel treatment is ineffective.
There are case reports of nitazoxanide being successfully used in human fasciolosis treatment in Mexico. There are also reports of bithionol being used successfully.
More recently, Mirazid, an Egyptian drug made from myrrh, has been investigated as an oral treatment of trematode-caused ailments including fascioliasis.
Nitazoxanide has been found effective in trials, but is currently not recommended. The life cycle includes freshwater snails as an intermediate host of the parasite.
The recommended treatment for people outside the United States is albendazole combined with ivermectin. A combination of diethylcarbamazine and albendazole is also effective. Side effects of the drugs include nausea, vomiting, and headaches. All of these treatments are microfilaricides; they have no effect on the adult worms. While the drugs are critical for treatment of the individual, proper hygiene is also required.
Different trials were made to use the known drug at its maximum capacity in absence of new drugs. In a study from India, it was shown that a formulation of albendazole had better anti-filarial efficacy than albendazole itself.
In 2003, the common antibiotic doxycycline was suggested for treating elephantiasis. Filarial parasites have symbiotic bacteria in the genus "Wolbachia", which live inside the worm and seem to play a major role in both its reproduction and the development of the disease. This drug has shown signs of inhibiting the reproduction of the bacteria, further inducing sterility.
Clinical trials in June 2005 by the Liverpool School of Tropical Medicine reported an eight-week course almost completely eliminated microfilaraemia.
Toxocariasis will often resolve itself, because the "Toxocara" larvae cannot mature within human hosts. Corticosteroids are prescribed in severe cases of VLM or if the patient is diagnosed with OLM. Either albendazole (preferred) or mebendazole (“second line therapy”) may be prescribed. Granulomas can be surgically removed, or laser photocoagulation and cryoretinopexy can be used to destroy ocular granulomas.
Visceral toxocariasis in humans can be treated with antiparasitic drugs such as albendazole or mebendazole, tiabendazole or diethylcarbamazine usually in combination with anti-inflammatory medications. Steroids have been utilized with some positive results. Anti-helminthic therapy is reserved for severe infections (lungs, brain) because therapy may induce, due to massive larval killing, a strong inflammatory response. Treatment of ocular toxocariasis is more difficult and usually consists of measures to prevent progressive damage to the eye.
A goal of community base efforts is to eliminate microfilariae from the blood of infected individuals in order to prevent transmission to the mosquito. This is primarily accomplished through the use of drugs. The treatment for "B. malayi" infection is the same as for bancroftian filariasis. Diethylcarbamazine (DEC) has been used in mass treatment programs in the form of DEC-medicated salt, as an effective microfilaricidal drug in several locations, including India. While DEC tends to cause adverse reactions like immediate fever and weakness, it is not known to cause any long-term adverse drug effects. DEC has been shown to kill both adult worms and microfilariae. In Malaysia, DEC dosages (6 mg/kg weekly for 6 weeks; 6 mg/kg daily for 9 days) reduced microfilariae by 80% for 18–24 months after treatment in the absence of mosquito control. Microfilariae numbers slowly return many months after treatment, thus requiring multiple drug doses over time in order to achieve long-term control. However, it is not known how many years of mass drug administration is required to eliminate transmission. But currently, there have been no confirmed cases of DEC resistance.
Single doses of two drugs (albendazole-DEC and albendazole-ivermectin) have been shown to remove 99% of microfilariae for a year after treatment and help to improve elephantiasis during early stages of the disease. Ivermectin does not appear to kill adult worms but serves as a less toxic microfilaricide.
Since the discovery of the importance of "Wolbachia" bacteria in the life cycle of "B. malayi" and other nematodes, novel drug efforts have targeted the endobacterium. Tetracyclines, rifampicin, and chloramphenicol have been effective in vitro by interfering with larvae molting and microfilariae development. Tetracyclines have been shown to cause reproductive and embryogenesis abnormalities in the adult worms, resulting in worm sterility. Clinical trials have demonstrated the successful reduction of "Wolbachia" and microfilariae in onchocerciasis and "W. bancrofti" infected patients. These antibiotics, while acting through a slightly more indirect route, are promising antifilarial drugs.
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.
There are two drugs available, praziquantel and oxamniquine, for the treatment of schistosomiasis. They are considered equivalent in relation to efficacy against "S. mansoni" and safety. Because of praziquantel's lower cost per treatment, and oxaminiquine's lack of efficacy against the urogenital form of the disease caused by "S. haematobium", in general praziquantel is considered the first option for treatment. The treatment objective is to cure the disease and to prevent the evolution of the acute to the chronic form of the disease. All cases of suspected schistosomiasis should be treated regardless of presentation because the adult parasite can live in the host for years.
Schistosomiasis is treatable by taking by mouth a single dose of the drug praziquantel annually.
The WHO has developed guidelines for community treatment based on the impact the disease has on children in villages in which it is common:
- When a village reports more than 50 percent of children have blood in their urine, everyone in the village receives treatment.
- When 20 to 50 percent of children have bloody urine, only school-age children are treated.
- When fewer than 20 percent of children have symptoms, mass treatment is not implemented.
Other possible treatments include a combination of praziquantel with metrifonate, artesunate, or mefloquine. A Cochrane review found tentative evidence that when used alone, metrifonate was as effective as praziquantel.
Another agent, mefloquine, which has previously been used to treat and prevent malaria, was recognised in 2008–2009 to be effective against "Schistosoma".
This applies once an infestation is established. In many circles the first response to cutaneous myiasis once the breathing hole has formed, is to cover the air hole thickly with petroleum jelly. Lack of oxygen then forces the larva to the surface, where it can more easily be dealt with. In a clinical or veterinary setting there may not be time for such tentative approaches, and the treatment of choice might be more direct, with or without an incision. First the larva must be eliminated through pressure around the lesion and the use of forceps. Secondly the wound must be cleaned and disinfected. Further control is necessary to avoid further reinfestation.
Livestock may be treated prophylactically with slow release boluses containing ivermectin which can provide long-term protection against the development of the larvae.
Sheep also may be dipped, a process which involves drenching the animals in persistent insecticide to poison the larvae before they develop into a problem.
The severe symptoms caused by the parasite can be avoided by cleansing the skin, surgery, or the use of anthelmintic drugs, such as diethylcarbamazine (DEC), ivermectin, or albendazole. The drug of choice is DEC, which can eliminate the microfilariae from the blood and also kill the adult worms with a dosage of 6 mg/kg semiannually or annually. A polytherapy treatment that includes ivermectin with DEC or albendazole is more effective than each drug alone. Protection is similar to that of other mosquito-spread illnesses; one can use barriers both physical (a mosquito net), chemical (insect repellent), or mass chemotherapy as a method to control the spread of the disease.
Mass chemotherapy should cover the entire endemic area at the same time. This will significantly decrease the overall microfilarial titer in blood in mass, hence decreasing the transmission through mosquitoes during their subsequent bites.
Antibiotic active against the Wolbachia symbionts of the worm have been experimented with as treatment. Wolbachia-free worms first become sterile, and later die prematurely.
Surgical removal or treatment with albendazole or ivermectin is recommended.
The most prescribed treatment for gnathostomiasis is surgical removal of the larvae but this is only effective when the worms are located in an accessible location. In addition to surgical excision, albendazole and ivermectin have been noted in their ability to eliminate the parasite. Albendazole is recommended to be administered at 400 mg daily for 21 days as an adjunct to surgical excision, while ivermectin is better tolerated as a single dose. Ivermectin can also serve as a replacement for those that can’t handle albendazole 200 ug/kg p.o. as a single dose. However, ivermectin has been shown to be less effective then albendazole.
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.