Heat rash

Identify it: Expose human skin to hot weather and heat rash is always a possibility. Heat rash happens when sweat ducts become blocked. Sweat can get blocked in several ways - by clothes that don't let the skin breathe, by sweating excessively, by a buildup of bacteria on the skin, or by sleeping under too many blankets. So the sweat that should come out of the skin gets trapped beneath the skin and causes lumps that can be pimply, blistery, and red. Some cases of heat rash have no other symptoms aside from the rash, while others can be intensely itchy and prickly, thus the rash's nickname, prickly heat.

Resolve it: Heat rash generally resolves on its own without needing any treatment. Still, if it develops, get out of the heat. Reduce activity. Sit in front of a fan to cool down. Take a cool shower. If need be, soothe the rash with calamine lotion. Should the rash get worse, or if it is accompanied by pain, pus, fever, chills, or other signs of infection, seek medical help. Repeated bouts of heat rash can advance to a point where the body doesn't sweat enough, increasing the risk of heat exhaustion.

Prevent it: To prevent the prickles, dress cool. Wear loose-fitting, light-coloured clothes made of natural fibres such as cotton that allow you to sweat as your body needs to. Avoid synthetics such as nylon or polyester - chafing, synthetic fabrics that are never at risk of being called "cool." Keep kids cool, too, by not overdressing them on hotter days.

Hot tub rash

Identify it: Bathe in a contaminated hot tub, spa, or swimming pool, and you could encounter Hot tub folliculitis. The human body is covered with hair follicles, the tiny pores out of which hair grows. Under certain circumstances (e.g., hot, wet conditions), a bacterium called Pseudomonas aeruginosa can come in contact with the hair follicles, causing an itchy, red, bumpy rash. The skin beneath your swimsuit may be especially susceptible, since the bacteria sits longer on that part of the skin.

Resolve it: Hot tub rash goes away on its own, unless you keep revisiting the contaminated tub or spa. Try an anti-itch medication if you're tempted to scratch. In severe cases, antibiotics may be needed to clear up any lingering infection.

Prevent it: Public hot tubs usually post advisories recommending that bathers take a shower before entering the water. Good advice! Take one after, too, just in case. Another way to protect yourself is to only bathe in sanitary tubs. A tub that smells bad or looks visibly dirty? Not so hot. If you're a home hot-tubber, regularly check the pH and disinfectant levels of your tub.

Swimmer's itch

Identify it: A rash that pops up within a couple of days of swimming in freshwater could be swimmer's itch. Exposed skin makes a temporary home for parasites that prefer ducks, snails, and other wetland animals. An allergic reaction to the tiny parasites causes a non-contagious rash that is red, raised, and, of course, itchy.

Resolve it: Swimmer's itch clears up quickly. Until it's gone, scratch the itch with calamine lotion, antihistamines, or anti-itch creams - not with your fingernails. Or soak in baths sprinkled with baking soda or Epsom salts. A rash that lasts longer than a week or that produces pus needs medical attention.

Prevent it: The parasites to blame for swimmer's itch thrive in warm bodies of water, especially lakes and ponds frequented by birds. So don't spend too much time swimming and wading in these types of waters. If you do swim in freshwater, stay out of the shallow areas, where more of the parasites hang out. After your swim, rinse your skin off and dry well.