Dehydration

Any hot and dry environment may cause dehydration in the body, so ensure that you drink adequate amounts of water before during and after an infrared sauna treatment.

Accelerated Body Temperature

Increased body temperature caused by the heat emissions of an infrared sauna may cause some unpleasant side effects in some, such as dizziness. While increasing the metabolism or rate at which the body burns calories for energy or fuel, infrared sauna bathers need to understand their own body and realize when your body may be experiencing adverse affects from the sauna, especially if you're not well. Move around every five minutes or so or rotate the body about 90 degrees every few minutes to ensure that not one part of the body is exposed to the heating source for long periods of time, suggests Dr. Lawrence Wilson, of The Center for Development.

Reddened Skin

Prolonged exposure to heat may cause reddened areas of skin, much like you'd experience from sitting outside in the sun too long or sitting too close to a heater. Limit your time in the sauna to prevent over-exposure. Read the manufacturer's information regarding guidelines, as the models and makers of different saunas may suggest different safe time lengths for sauna-bathers.

Heart Conditions

Sitting in a sauna may exacerbate some heart conditions, suggests the National Institutes of Health. Before you consider sitting in a sauna, talk to your doctor about its safety, especially if you've been diagnosed with any type of heart condition or blood pressure issues. Heat may cause the heart rate to accelerate, leading to added strain or stress on the heart and blood vessels.

Other Adverse Affects

Avoid drinking any alcohol before and during sauna use, as alcohol may disrupt reasoning, leading you to stay in the sauna longer than is safe. Oxygen deprivation, heart irregularities such as arrhythmia and decreased blood pressure caused by excessive amounts of alcohol in the blood may also lead to faintness and even collapse.