Dr. Keith Roach:DEET, others effective insect repellents
Dear Dr. Roach: I am concerned about Zika virus and other mosquito-borne illnesses. What is the best way to keep mosquitos from biting?
Dear K.P.: One way is to stay away from where the mosquitos are, especially sources of stagnant water. They are most active at sunrise and sunset, so it’s especially important to stay away then. Protective clothing is also helpful.
According to a recent study, the most effective insect repellent is DEET, with 25 to 35 percent solutions being the optimum balance between effectiveness and skin irritation for most people. DEET has been in use for more than 50 years, and multiple studies have confirmed its safety.
Alternatives include picaridin and IR3535. One other alternative is an extract from the lemon eucalyptus plant, which is about as effective as DEET products.
Dear Dr. Roach: My blood pressure is controlled with medication. My husband has bad psoriasis. Is a hot tub safe for us?
Dear M.F.: The use of a hot tub by someone with well-controlled hypertension is generally considered safe. A hot tub (or sauna) causes blood vessels in the skin to dilate (enlarge), which can cause a small drop in blood pressure. If the blood pressure is excessively controlled, this can cause some lightheadedness. However, a brief time (10 minutes) in a hot tub caused no problem in a group of hypertensive people who were well-treated.
For psoriasis, the use of a hot tub helps some people and makes other people have more flare-ups. It can be excessively drying to the skin, so moisturizing afterward is a good idea.
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