Immersion foot aka "Trench Foot" is an injury to the feet that comes from being wet for too long of a period. The feet become swollen and painful. If untreated it can cause a person to become lame.
Signs & Symptoms
Symptoms of immersion foot are nearly the same as for frostbite. The feet will first feel damp or, if severely wet, will slosh in your footgear. Then your feet may itch or become tender. Wrinkling and blisters may form which may crack and bleed. After a while the feet will feel heavy and even become numb. After removing your footgear the affected foot/feet may swell. If ignored the foot may become infected or gangrenous requiring amputation.
Prevention & Treatment
When possible, air-dry and elevate your feet, and exchange wet shoes and socks for dry ones to help prevent the development of immersion foot. Use foot powder to help keep your feet from becoming too sweaty. Avoid using cotton socks next to the skin.
Treatment for immersion foot is similar to the treatment for frostbite. Take the following steps:
Thoroughly clean and air dry your feet. Do not rub vigorously or towel dry.
Treat the affected part by applying warm packs or soaking in warm water (102° to 110° F) for approximately 5 minutes. When sleeping or resting, do not wear socks.
If you must walk any distance apply moleskin to any blisters, put on clean dry socks and footgear.
Obtain medical assistance as soon as possible.
If you have a foot wound, your foot is more prone to infection. Check your feet often for infections or worsening of symptoms.