antibioticsbooks

278 PART 6 Antiparasitic Drugs
Spectrum
Ectoparasites: Sarcoptes scabei (scabies mite),
Pediculus humanus (lice)
Nematodes (roundworms): Onchocerca vovulus
(river blindness), Strongyloides stercoralis
(strongyloidiasis), Ancylostoma brazilense
(cutaneous larva migrans), other nematodes
Adverse Effects
In treatment of scabies, ivermectin is very well tolerated.
Severe adverse reactions, including fever,
myalgia, and hypotension, have been reported
when ivermectin is used for management of nematode
infections in endemic settings. These effects
are thought to be a result of the host’s immune
response to antigens released from killed parasites.
These effects are more severe in patients with
higher worm burdens, and they generally resolve
soon after drug administration.
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Important Facts
• Yes, ivermectin is the same drug you use to
treat your dog’s heartworms. It is also at the
center of a heartworming story: after ivermectin
was shown to be effective as a once-yearly
treatment for river blindness, the pharmaceutical
company Merck offered to donate—
free of charge—as much ivermectin as was
needed to treat the disease. It is estimated
that 200 million free treatments have been
provided to date, avoiding more than half a
million cases of blindness. Hey, at this point in
the book, we figured you could use some good
news (and bad puns).