Are there negative effects associated with insect repellant?

Not really: I'm sure you can find something on the internet that says that insect repellants are killing us all, but I use them. Some people feel that an ingredient called deet is unhealthy, but it does work. And while there might be some small unknown risk, what about the known risk of insect bites and associated diseases? I say go for it...The benefit is worth the risk.

Yes: There can be serious side effects associated with some insect repellents. Specifically, deet, which is in many repellents and has been on the market since 1956, can cause problems if not used correctly. Reported severe reactions have included seizures and death (after ingestion). The cdc recommends: use sparingly & never on wounds, low conc in kids, no ingest/inhaling, apply to clothing if can.