No, it's not an allergy; an allergic reaction involves the release of histamines, which are directly implicated in
inflammation. Anti-histamine medications, including those sold over-the-counter, can be helpful.
What you describe sounds like a chemical reaction (I've had enough of them to recognize at least one set of symptoms, unfortunately). I just went to the website of
one citronella candle manufacturer and found--as usual--that 0.5% of the item is "Oil of citronella." The other 99.5% of the compound, termed "inert ingredients," are specified. However, the three listed "inert ingredients" seem unlikely to be the whole story: "Soybean Oil, Palm Oil, Paraffin Wax [sic]."
Often, what we react to is something unrevealed in the "inert" ingredients, perhaps a volatile organic compound (VOC) or other potentially toxic compound. Toxicity is dose-dependent, but many people have thresholds lower than the regulations admit for a chemical reaction. (Canada is phasing out citronella as an insecticide due to toxicity data-gap concerns, according to
Wikipedia; the European Union phased out all use of citronella as an insect repellent in 2006.)
I've dealt with VOCs as well as I can in my own home, but am at the mercy of others whenever I go out in public: perfumes, after-shave lotions, quick-light BBQ briquets in the neighbors' yards--anything like these can bring on either a "two-inhale" migraine or a respiratory "freeze" where I can neither inhale nor exhale. The respiratory "freeze" isn't asthma (one of my sisters had asthma all of our childhood), and it's not anything I can re-create in the doctor's office, either, to help
her make a diagnosis. But it's definitely a reaction to chemicals; it's too immediate to be anything else.
Surely Native Americans/First Nations people had protection against mosquitoes. I wonder what it was?
Cynthia H.
Sunset Zone 17, USDA Zone 9