It is used, among other applications, for the production of long-lasting insecticidal nets (LLINs), which, along with indoor residual spraying (IRS), are the main vector control strategies recommended by the World Health Organization (WHO) for the management of malaria.

Resistance has been identified in several insects, including important vectors of malaria like the mosquito Anopheles gambiae as well as non-disease carrying pests like bed bugs.

Characterization of the different forms of resistance among mosquitoes has become a top priority in groups studying tropical medicine due to the high mortality of those who reside in endemic areas.

If taken in through the eyes or mouth, the most common symptom is facial paraesthesia, which can feel like many different abnormal sensations, including burning, partial numbness, "pins and needles", skin crawling, etc.

There is one case report describing chronic intoxication from pyrethroid insecticides leading to a syndrome clinically similar to motor neuron disease.

[6] A 2015 study conducted in Brittany, France, found a negative correlation between deltamethrin exposure (measured through the presence of a metabolite in urine) and cognitive scores in infants.