Head Lice Flashcards
How do chemical methods differ from physical methods?
Chemical - paralyze the louse and cause fatal dehydration
Physical - suffocate the louse
What is the only ovicial therapy?
malathion
MOA of malathion
organophosphate insecticide; in louse - metabolized to malaoxon (inhibits Achesterase = neuronal hyperstimulation)
adverse effects of malathion
only from oral/pulmonary ingestion – leads to increased GI peristalsis, decreased ocular accommodation/pain; rhinorrhea; chest tightness/wheezing; increased lacrimation, salvation and sweating; bradycardia, etc
What is the treatment for malathion ingestion in humans?
atropine and pralidoxime
MOA of permethrin
paralysis by binding voltage-gated Na channels
adverse effect of permethrin
asthma exacerbation in pts allergic to ragweed
how can reistance against permethrin arise?
knock-down resistance mutations to louse Na channels
what happens to permethrin when it reaches our systemic system
inactivated by ester hydrolysis
MOA of lindane
blocks GABA action
adverse effects of lindane
neurotoxicity b/c drug is CNS stimulant = seizures
what is the BBW for lindane?
skin dz/condition or neonatal prematurity will increase drug systematization; CI in pts w/ uncontrolled seizure disorders
MOA of ivermectin
binds to glutamate-gated Cl channels and causes hyperexcitability and paralysis in invertebrae nerve and muscle cells
who is ivermectin not given to?
to younger individuals who have an immature BBB
adverse effect of ivermectin
worsens bronchial asthma
