The hot water bottle is a container filled with hot water and sealed with a stopper to provide warmth usually in bed, but also for therapeutic applications of heat to a specific part of the body. In the past, early hot water bottles were made of various materials such as zinc, copper, glass, or wood. In order to prevent burning, they were wrapped in a soft cloth bag.

Modern hot water bottles are manufactured with rubber or similar materials, from a design created and patented by the Croatian inventor Eduard Penkala in 1903. By the end of the century, the use of hot water bottles declined due to newer items such as electric blankets and other heating systems. 

The application of hot water bottles in the body is considered a type of heat therapy, also called thermotherapy. Hot water bottles can be used to decrease pain, muscle spasms, and joint stiffness, and increase local tissue metabolism. In addition, the use of hot water bottles promotes relaxation, promotes vasodilation, accelerates healing, and lowers skin impedance, while allowing oils, creams, and ointments to deeper penetrate into the skin. However, hot water bottles should not be used in the acute stage of an injury because they may worsen edema (swelling caused by the accumulation of too much fluid in the body’s tissues) and inflammation.

Hot water bottles produce heat superficially less than half an inch deep into the skin. Heat increases the rate of metabolic activity, which increases oxygen consumption and phagocytosis (cellular process for ingesting and eliminating foreign microorganisms). Elevation in tissue temperature is also associated with vasodilatation and a rise in blood flow to the area that helps provide nutrients and leukocytes (blood cells of the immune defense system) to that area, increasing capillary permeability (passing through) and fluid exchange.

Instructions: Unscrew the plug from the hot water bottle. Carefully fill with hot water about 2/3 full. Before screwing the plug back, make sure to squeeze out the remaining air. Do not squeeze too hard to avoid spillage. Make sure the plug is back on securely before use. Apply hot water bottle to the desired area of the body using a towel or cloth between the bottle and skin.

Caution: Do not fill the hot water bottle with boiling water. Do not use microwave or conventional oven. Be sure to test for leakage before use. Do not fold, sit on or lie on. When applying to sensitive areas or bottle feels too hot, wrap the bottle with a soft cloth or towel. Do not use this product if pregnant or nursing. If symptoms persist, consult a doctor. Keep this product out of reach of children.

Storage: Before storing the hot water bottle, empty all the water and allow to air dry.

The statements above have not been evaluated by the Food and Drug Administration (FDA).
This product is not intended to diagnose, treat, cure or prevent any disease.