Medical Q&As

Insect repellents - which one?

I am travelling to Tunisia for my holidays. Could you give me the name of a good safe insect repellent?

I want to clarify at the outset of this answer that you are not at risk of acquiring malaria on your holiday to Tunisia. However, you are at risk of being bitten by mosquitoes as you would in many other warm but non-malaria affected areas. There are many insect repellents available to the public for sale OTC (over the counter). The New England Journal of Medicine, which is one of the most respected medical journals in the world, published a paper this summer on this very subject. The authors compared various products to establish which products provided reliable and prolonged protection from mosquito bites. The products included several botanical insect repellents, several synthetic repellent sprays, several different impregnated wristbands and a moisturiser that was claimed to have repellent effects. Testing of the various insect repellents was conducted under controlled conditions on a group of volunteers. The mosquitoes that were used for the research were kept in controlled conditions of temperature, humidity and light. The researchers then set their stopwatches and timed how long it took for the volunteers to be bitten. Products containing DEET (diethylmethyltoluamide) provided the best protection from being bitten by the mosquitoes. One formulation containing 23.8% DEET had an average protection time of 5 hours whereas the natural botanical sprays provided protection for an average of 20 minutes. Wristbands impregnated with repellent offered no protection at all. The conclusion of the study was that DEET containing repellents scored best in terms of duration of effectiveness. The reason that mosquitoes were chosen as the insect for the study is because they are important vectors in a number of serious diseases. When you go to your pharmacy specify that you want an insect repellent containing DEET. Also make sure that you donít wear perfumed products such as eau de toilette, aftershave, perfume or scented antiperspirants because the scent contained therein may counter the effect of the insect repellent and actually attract mosquitoes.