Water has been used medicinally for thousands of years, with traditions rooted in ancient China, Japan, India, Rome, Greece, the Americas, and the Middle East. There are references to the therapeutic use of mineral water in the Old Testament. During the Middle Ages, bathing fell out of favor due to health concerns, but by the 17th Century, "taking the waters" at hot springs and spas became popular across Europe (and later in the United States).
Hydrotherapy is broadly defined as the external application of water in any form or temperature (hot, cold, steam, liquid, ice) for healing purposes. It may include immersion in a bath or body of water (such as the ocean or a pool), use of water jets, douches, application of wet towels to the skin, or water birth. These approaches have been used for the relief of various diseases and injuries, or for general well-being. There are other therapies that may include the use of water as a part of a technique, such as colonic irrigation, enemas, nasal irrigation, physical therapy in pools, steam inhalation, humidifiers, drinking of mineral water or "enriched" water, coffee infusions, aquatic yoga, aquatic massage (including Watsu®), or aromatherapy or baths with added essential oils, however, they are not discussed in-depth in this review.
Modern hydrotherapy originated in 19th Century Europe with the development of spas for "water cure" ailments, ranging from anxiety to pneumonia to back pain. Father Sebastian Kneipp, a 19th Century Bavarian monk, spurred a movement to recognize the benefits of hydrotherapy. His methods were later adopted by Benedict Lust, who immigrated to the United States from Germany in 1896 and founded an American school of naturopathic medicine. Lust claimed to have cured himself of tuberculosis with Kneipp's methods, and so hydrotherapy was included as a component of naturopathic medicine. In the present day, a wide variety of water-related therapies are used, some of which are described below.
Aquatic physical therapy/Watsu®: Physical therapy in pools is a well-established technique that takes advantage of buoyancy and resistance to movement in water. Watsu® is a Chinese form of bodywork conducted in pools.
Coffee infusions: The use of coffee infusions was developed by Dr. Max Gerson. It is thought to stimulate intestinal contractions and is used in cases of indigestible food and nausea.
Cold arm bath: For a cold arm bath, the arm is placed in a basin of cold water with the water level reaching just above the elbow.
Cold footbath: Cold footbaths involve placing the feet in a bath filled calf-deep with cold water. "Walking in water" involves stepping on a nonslip mat placed under water.
Cold rubbings: This technique may use linens or towels soaked in cold water then wrung out and vigorously rubbed on the upper and lower trunk or the entire body.
Cold water therapy (60 degrees Fahrenheit): Cold water therapy is used to stimulate blood flow in the skin and underlying muscles.
Colonic hydrotherapy: Colonic hydrotherapy uses water as a vehicle to eliminate toxins and wastes in the colon, which are either immobilized in pockets or glued to its sides. Colonic hydrotherapy frees the intestinal tract of organic wastes. During colonic irrigation, a therapist inserts a plastic tube into the person's rectum and pumps water or herbal solutions until the colon is full (called an enema). Once the colon is full, the therapist massages the abdomen area and then draws the fluid out. The procedure is repeated for up to an hour. Body-temperature water is used. Some experts in the field claim this treatment is unnecessary and possibly harmful.
Constitutional hydrotherapy: Constitutional hydrotherapy is hydrotherapy used on the whole person, usually by being wrapped in sheets and blankets of varying temperatures. Constitutional hydrotherapy is thought to reestablish normal brain function.
Dead Sea balneotherapy: There are numerous published articles regarding the use of therapeutic uses of water immersion in the Dead Sea (and other salt water bodies), particularly for chronic skin conditions. Because this therapy also involves prolonged exposure to sunlight, it is not clear to what extent possible benefits are due to the water, to minerals and high salt content in the water, to sun exposure, or to a combination of factors.
Douches: Douches may be carried out with a watering can or hose. Treatments may be applied to any area of the body, with the intention to relieve tension or pain, or to affect blood flow.
Hot fomentation: Hot fomentation involves application of warm liquid or moist heat to the surface of the body. Practitioners believe that this enhances the body's ability to fight cancer cells, viruses, and bacteria. This therapy is often used to relieve fever, because it raises the body temperature to 101-103 degrees Fahrenheit, which is suggested to reestablish the natural fever cycle, allowing the body to heal itself.
Hot water therapy: Hot water therapy (around 100 degrees Fahrenheit) is used to relax muscles and cause sweating. It is commonly used for arthritis, rheumatism, poor circulation, and sore muscles.
Internal hydrotherapy: Internal hydrotherapy consists of colonic irrigations and enemas. It also includes steam baths or inhalation of steam to relieve respiratory congestion, and drinking mineral water to restore electrolyte balance or cleanse the system.
Local hydrotherapy: Local hydrotherapy is hydrotherapy used on one part of the body.
Packs: Cold or warm packs are applied to treat certain muscular, joint, or psychiatric conditions.
Poultices: Poultices are used for health maintenance and treatment of disease.
Purifying baths: Purifying baths include bathing in solutions of chlorine bleach, sea salt, lemon juice, turmeric, Epsom salts, baking soda, or other substances in order to purify the body of radiation, toxins, or heavy metal deposits.
Rising-temperature arm bath: In the rising-temperature arm bath, arms are immersed in a bath with water at body temperature. Hot water is gradually added until the temperature reaches 103-104 degrees Fahrenheit. The whole process lasts for 10-15 minutes and may be done daily. Caution is warranted so as not to cause burns.
Rising-temperature footbath, warm footbath: In these baths, feet are immersed in water at body temperature. Hot water is gradually added until the temperature reaches 103-104 degrees Fahrenheit. The process lasts for 10-15 minutes and may be done daily. Caution is warranted so as not to cause burns.
Rising-temperature hip bath: These baths are administered in tubs initially filled with shallow, tepid water. Hot water is gradually added until levels reach the navel. A common temperature is 103-104 degrees Fahrenheit. Caution is warranted so as not to cause burns. The bather may then be wrapped in warm dressings.
Shower: Hot, cold, or alternating-temperature sprays are commonly used.
Sitz bath: A sitz bath is administered in a tub that allows the hips to be immersed in water. Sitz baths have been used in the management of back pain, sore muscles, muscle spasms, body aches, sprains, hemorrhoids, pruritus (itching), inflammation, rashes, and anxiety; for wound care and hygiene; and for relaxation. For various ailments, different temperatures may be used, and minerals or medications may be added to the water.
Spa/hot tub/whirlpool/motion-based hydrotherapy: These therapies are sometimes used in people with wounds, chronic musculoskeletal pain, or inflammation. Awareness of the risk of introducing infections into wounds and keeping wounds clean is important.
Steam bath/sauna: Heat may be used to cause sweating, and this technique is variably included in the definition of hydrotherapy. People should not spend more than 15-20 minutes in a steam bath or sauna, and individuals with medical conditions such as heart or lung disease should avoid prolonged heat exposure (as directed by a qualified healthcare provider).
Stanger bath therapy: Stanger bath therapy consists of application of a current through metal electrodes placed in a special water tub. It is most often used in the relief of pain.
Water birth: The potential benefits of giving birth in water have been explored. Water births may be as safe as vaginal births if they are conducted by experienced professionals with low-risk women.
Wraps: Hot or cold wet wraps may be used around various parts of the body. This technique is sometimes used with the intention to reduce fever or foster relaxation. Hot fomentation involves the application of warm liquid or moist heat with towels to the surface of the body.
Aqua lymphatic therapy, aquatic physical therapy, balneopelotherapy, balneoradonokinesitherapy, balneotherapy, bath, climatotherapy, cold therapy, cold water cure, colonic hydrotherapy, colonic irrigation, constitutional hydrotherapy, crenotherapy, Dead Sea bath, douche, dry-air radon bath, external hydrotherapy, fomentation, footbath, home spa, hot springs, hot therapy, hot tub, hot tub therapy, ice water immersion, immersion bath, internal hydrotherapy, Jacuzzi®, jet spray, local hydrotherapy, motion-based treatment, mud bath, pack, poultice, purifying bath, radon and iodine-bromine baths, radon bath, salt bath, saltwater baths, sauna, sauna bathing, shower, siliceous baths, sitz bath, soaked towel, spa treatment, specialized bathing systems, Stanger bath therapy, sulfide mud, temperature-based treatment, therapeutic bath in mineral water, thermal spring water, thermal therapy, Turkish bath, warm saltwater immersion, warm sulfur water immersion, warm tap water immersion, water bath, water birth, water immersion, water mineral bath, Watsu®, whirlpool, whirlpool bath.
Note: This review does not include in-depth discussions of therapies that may include the use of water as a part of the technique, such as colonic irrigation, enemas, nasal irrigation, physical therapy in pools, steam inhalation, humidifiers, drinking of mineral water or "enriched" water, coffee infusions, aquatic yoga, aquatic massage (including Watsu®), or aromatherapy or baths with added essential oils.