A good sweat session is often associated with intense exercise like running, cycling, or strength training, but you can also warm things up while relaxing and rejuvenating in an infrared sauna.

Known for easing sore muscles, improving sleep, and general relaxation, infrared saunas are a top choice for people looking for a cooler way to heat their bodies.

While considered safe for most people, there are some risks associated with using an infrared sauna.

Here’s what you need to know before you dress down and get in for a quick session.

If you’re a fan of dry heat, there’s a good chance you’ve spent time using a traditional sauna. These saunas heat the air around you and typically operate at a temperature of 180°F to 200°F (82.2°C to 93.3°C).

According to the North American Sauna Society, the majority of saunas you see in homes and commercial settings use electric sauna heaters.

However, the infrared sauna, which uses electromagnetic radiation from infrared lamps to warm your body directly rather than heating the air, is gaining popularity.

“Infrared saunas heat your core body temperature and only heat to about 150°F (66°C),” says Dr. Fran Cook-Bolden, MD, FAAD, with Advanced Dermatology P.C.

Cook-Bolden says this type of heat penetrates deeper into the body and is thought to impact and heal deep tissue and also detox via sweating through your pores.

The reported benefits of using an infrared sauna, including better sleep and relaxation, are impressive. Relief from sore muscles reportedly tops the list.

But just like anything else, with the pros come the cons. Before you heat up, take note of these potential side effects and risks.

According to a 2018 systematic review, the negative signs and symptoms of sauna use include:

One small 2013 study found that continuous sauna exposure, which consisted of 2 sauna sessions per week for 3 months — each lasting 15 minutes — demonstrated impairment of sperm count and motility.

Dr. Ashish Sharma, a board-certified internal medicine physician and hospitalist at Yuma Regional Medical Center, also shared insight regarding negative side effects linked to sauna use.

Dr. Sharma says the dry heat generated in an infrared sauna can cause you to become overheated, and if used for a prolonged session, it can also cause dehydration and even heat exhaustion or heat stroke.

In general, infrared saunas are considered safe for most people.

However, if you’re on medications, have implanted medical devices, or have a medical condition — whether acute or chronic — you should be cautious.

Cook-Bolden says you should speak to your healthcare provider before encountering any form of intense heat exposure.

Cook-Bolden says these conditions make people more prone to dehydration and overheating:

  • having low blood pressure
  • having kidney disease
  • taking medications such as diuretics, other blood pressure-lowering drugs, or medications that can cause dizziness

While not an exhaustive list, the conditions listed in this section warrant avoiding infrared sauna use or getting clearance from a healthcare provider.

  • Nerve and motor function conditions. If you have a neurological deficits, Cook-Bolden says your ability to sense and respond to the intensity of heat might put you at risk for heat or burn injuries.
  • Pregnancy considerations. If you’re pregnant, avoid using the sauna unless you’ve received clearance from your doctor.
  • Age considerations. If you have an age-related limitation, avoid using a sauna. This includes older adults who are more prone to dehydration and dizziness with dry heat, which can lead to falls. For children, discuss infrared sauna use with their doctor before trying it out.
  • Weak or compromised immune system. If you have a weakened immune system, Cook-Bolden says you should contact the facility to make sure it’s well-kept and that it has strict cleaning protocols and procedures in place that meet industry standards. Afterward, talk with your healthcare provider to get clearance to use the facility.
  • Unhealed wounds. If you have open wounds or you’re recovering from surgery, wait until these areas are healed. Then talk with your healthcare provider first to get permission before getting infrared sauna treatments.
  • Heart conditions. “People with cardiovascular diseases, or underlying heart arrhythmia such as atrial fibrillation, should talk with their doctor before using a sauna,” Sharma says. The use of a sauna can increase heart rate and cause arrhythmia.

If the risks outweigh the benefits, Sharma says, remember the benefits of saunas are mainly because of the physiological effects of sweating and increased heart rate, just like moderate exercise.

“If you cannot tolerate the sauna or do not have an infrared sauna available where you live, you can also get similar — and even more — health benefits by doing cardiovascular and strength training workouts,” he adds.

Whether you’re using an infrared sauna at a health club, spa, or at home, it’s important to follow the general guidelines for safe use. Here are some tips to get you started.

  • Seek medical clearance. Although there’s evidence supporting the notion that infrared sauna treatments can be beneficial, Cook-Bolden says it’s best to seek the advice of your healthcare provider before using the sauna. This is especially true if you have any conditions that may be contraindicated.
  • Avoid drinking alcohol. Drinking alcohol prior to sauna use can cause overheating and potentially lead to dehydration, a heat stroke, and heat exhaustion. “Due to its dehydrating nature, it’s best to avoid alcohol consumption beforehand,” says Cook-Bolden.
  • Drink plenty of water. Make sure you drink plenty of water before getting in the sauna, during your session — especially if you start feeling light-headed or thirsty, or you find yourself sweating excessively, and also when you get out.
  • Start with mini sessions. Begin with mini sessions that last approximately 10–15 minutes. As you get comfortable, you can add time to each session until you reach 20 minutes. Depending on your access to the sauna and overall goal, 3 sessions a week seems to be the average number for most people.
  • Avoid use with irritated skin. If you have a sensitive skin condition or a condition such as eczema than can cause skin irritation, Cook-Bolden says you may want to allow your skin to recover before exposure.
  • Pay attention to certain symptoms. If you experience symptoms of dizziness or light-headedness, stop your session immediately. Sharma says this can be a sign of dehydration or other medical complications. And if the symptoms persist, he recommends seeking immediate medical assistance.

Infrared saunas provide a relaxing experience that’s safe for most people. That said, they’re not appropriate for everyone.

If you’re pregnant, young, an older adult, at risk of overheating or becoming dehydrated, or you have a chronic health condition, you may want to avoid using an infrared sauna.

These conditions can increase your risk of further health complications. Consider your current health status and talk with your healthcare provider before using an infrared sauna.