Adverse effects ivermectin

Thiabendazole is much more toxic than other benzimidazoles and more toxic than ivermectin, so other agents are now preferred for most indications. Common adverse effects include dizziness, anorexia, nausea, and vomiting. Less common problems are epigastric pain, abdominal cramps, diarrhea, pruritus, headache, drowsiness, and neuropsychiatric symptoms. Irreversible liver failure and fatal Stevens-Johnson syndrome have been reported. 

Over a number of years, ivermectin has shown excellent results in the treatment of onchocerciasis, both in controlled studies and in the field, including use in the WHO-sponsored program of treatment. This experience has provided a thorough picture of its adverse effects. The effective dosage is of the order of 50-200 micrograms/kg. After a single oral dose, skin microfilariae remain at low levels for up to 9 months. 

As antihehninthic drugs go, ivermectin can be considered a reasonably safe drug, and it is generally better tolerated than diethylcarbamazine. Clinical experience has often shown relatively little toxicity, although mild adverse effects, presumably due to the kilting of the microfilariae, involve at least one-third of patients some work has suggested that neutrophil activation may play a role in the development of these reactions (1). It has also been well tolerated in combinations, for example when given with albendazole in order to kill adult worms (which cannot be achieved with ivermectin alone) or with diethylcarbamazine for bancroftian filariasis (SEDA-20, 281). 

The use of ivermectin and its adverse effects in patients infected with Loa loa have been reviewed (7). It was concluded that ivermectin in a single dose of 150-300 micrograms/kg is effective in reducing microfilaria counts by over 90% with suppressed counts to 25% of pretreatment values after 1 year. An even more... 

The efficacy and adverse effects of ivermectin 200 micro-grams/kg, repeated 2 weeks later, have been stndied in 50 patients with chronic strongyloidiasis, aged 30-79 years (13). The eradication rate was 96% at 2 weeks after the first dose and 98% after the second dose. There was no recurrence after follow-up of 4 months. One patient had nausea and vomiting 3 hours after the first dose and again after the second dose, but they were transient and required no therapy. In four patients there were mild laboratory abnormalities (slight increases in liver function tests in two, microscopic hematuria in one, and mild leukopenia and lymphocytosis in one). Of the 50 patients 12 were positive for human T lymphotropic virus type-I. 

In 80 children aged 6 months to 14 years a single dose of ivermectin 200 micrograms/kg was compared with topical benzyl benzoate for the treatment of pediatric scabies in a randomized, controlled trial (17). Ivermectin cured 24 of 43 patients and topical benzyl benzoate cured 19 of 37 patients at 3 weeks after treatment. There were no serious adverse effects with either treatment, although benzyl benzoate was more likely to produce local skin reactions. These results are in line with those of another study, in which 18 children aged 14 months to 17 years with either scabies (n — 11) or cutaneous larva migrans (n — 7) were... 

A 39-year-old Afro-Caribbean man with stage IVB T cell Ijmphoma due to HTLV-1 infection had invasive Strongyloides hyperinfection that did not respond to oral ivermectin plus albendazole because of concurrent ileus. He was treated with two 6 mg doses of a veterinary formulation of ivermectin subcutaneously. There were no adverse effects, apart from pain at the injection site. 

In dogs and cats, seven monthly treatments of 60 mg kg (10 times the recommended dose) produced no adverse reactions when given to 6-week-old kittens or puppies. An exposure of ISmgkg (3 x dose) produced no effect on reproduction in females or males. Three monthly doses of 30 mg kg produced no adverse effects in ivermectin sensitive collies. There have also been rare reports of muscle spasms, seizures, ataxia, and other neurological signs. 

In our clinical use of ivermectin, more than 400 patients were studied. Administration was discontinued in only 2 patients due to liver dysfunction. Few subjective symptoms that were clinically problematic were observed. Thus, the rate of eradication obtained with ivermectin was excellent, and its incidences of adverse effects and liver dysfunction were low and their severity was mild. 

M. Iwasa, T. Maruo, M. Ueda and N. Yamashita, Adverse effects of ivermectin on the dung beetles, Caccobius jessoensis Harold, and rare species, Copris acutidens Motschulsky (Coleoptra Scarabaeidae), in Japan, Bull. Entomol. Res., 2007, 97, 619-625. 

Ivermectin was generally well tolerated. Quantitative pupillometry ruled out any mydriatic effect of ivermectin. There was no nervous system toxicity associated with oral ivermectin at any of the doses. There were no serious clinical or laboratory adverse events. Three of the fifty-one subjects who took ivermectin fasted reported minor adverse gastrointestinal events fecal abnormality (n = 1), nausea (n = 1), and vomiting (n — 1) six reported minor neurological adverse events headache (n = 4), anxiety n — V), and dizziness n — 1). There were no adverse events in the subjects who took ivermectin 120 mg. The absorption of ivermectin was about 2.5 times higher when it was given after a high-fat meal. 

For mass treatmerU programs, the introduction of diethylcarbamazine into table salt (0.2-0.4% by weight of the base) has markedly reduced the prevalence, severity, and transmission of lymphatic filariasis in many endemic areas. Diethylcarbamazine given annually as a single oral dose of 6 mg/kg is most effective in reducing microfilaremia when coadministered with either albendazole (400 mg) or ivermectin (0.2-0.4 mg/kg). Adverse reactions to microfilarial destruction usually are well tolerated. However, mass chemotherapy with diethylcarbamazine should not be used in regions where onchocerciasis or loiasis coexist because it may induce severe reactions related to parasite burden in these infections. 

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