Infrared saunas are generally safe for most people, but there are certain individuals and circumstances where sauna use is not recommended or should be done with caution. The gentle heat of an infrared sauna is well-tolerated by many, but it still poses stress on the body (raising core temperature, altering blood pressure, etc.).
People Advised Not to Use Saunas
Here are the groups of people who should avoid or get medical clearance before using an infrared sauna, and the reasons why:
1. Pregnant Women
Pregnant individuals are usually advised to avoid saunas (infrared or traditional). The primary concern is that raising the core body temperature, especially in the first trimester, has been associated with an increased risk of birth defects. The American College of Obstetricians and Gynecologists specifically recommends against activities that can cause overheating during pregnancy (like hot tubs and saunas) because the fetus cannot regulate its temperature, and high maternal body temperature (hyperthermia) in early pregnancy might contribute to neural tube defects or other issues.
Later in pregnancy, overheating can also lead to dehydration or fainting in the mother, which could indirectly stress the baby. So, to be safe, pregnant women should steer clear of saunas. If a pregnant person wants to use one, they should get clearance from their OB/GYN, keep sessions very short and at lower temperatures, but generally it’s better to just avoid it.
2. People with Uncontrolled High Blood Pressure or Heart Conditions
Individuals with poorly controlled hypertension (high blood pressure) or significant cardiovascular issues (like arrhythmias, unstable angina, recent heart attack, advanced heart failure) should be very cautious with saunas. Saunas cause vasodilation (widening of blood vessels) which can drop blood pressure during or after the session.
For someone whose blood pressure is not well managed, this could lead to dizziness or fainting. On the flip side, the heat and increased heart rate could potentially put strain on the heart. People with serious heart diseases should consult a cardiologist before sauna use. Interestingly, some studies show that stable heart patients can benefit from moderate sauna use (improved blood vessel function), but it must be done under guidance.
Unstable heart conditions or severe aortic stenosis are definite no-gos – the sudden changes in blood pressure could be dangerous. Also, if you have a pacemaker or other implanted cardiac device, check with a doctor; infrared saunas shouldn’t typically affect them, but it’s wise to confirm.
Still, infrared saunas can be beneficial for cardiovascular health for most people.
3. Individuals Prone to Low Blood Pressure or Dizziness
If you tend to have low blood pressure or get orthostatic hypotension (dizzy upon standing), be careful in saunas. The heat can cause your blood pressure to drop further. When you stand up out of the sauna, you might be at risk of fainting.
Elderly folks, in particular, who often have lower blood pressure, should limit sauna time and make sure to stand up slowly and have someone nearby if needed. Dr. Adolph Hutter from Harvard notes that older people with blood pressure on the low side need to be extra careful in hot baths or saunas. This doesn’t mean they absolutely can’t use them, but caution is warranted.
4. People with Severe Dehydration or Illness
If you’re already dehydrated, have diarrhea, or are sick with a fever, you should avoid the sauna. Saunas will dehydrate you further (through sweating) and if you have a fever, raising your body temp more is not wise. Also, when you’re ill (flu, COVID-19, etc.), a sauna won’t “sweat out” the illness; it could make you feel worse or strain your body. It’s better to rest and recover, and use the sauna when you’re healthy again.
5. Those with Heat Sensitivity or Multiple Sclerosis
People with certain neurological conditions, like multiple sclerosis (MS), often have heat intolerance. In MS, a slight increase in body temperature can temporarily worsen symptoms (this is known as Uhthoff’s phenomenon).
Because nerves that have lost their myelin conduct signals even less efficiently when hot, MS patients might experience blurred vision, extreme fatigue, or weakness in a hot environment. Therefore, many doctors say individuals with MS should avoid hot tubs and saunas or only use them very briefly at mild temperatures.
Similarly, those with other conditions that make them sensitive to heat (some people with dysautonomia or who easily get heat exhaustion) should be cautious.
6. People with Open Wounds, Severe Skin Conditions, or Recent Surgery
If you have a significant open wound or a large burn, being in a sauna could aggravate it or increase risk of infection (warm, moist environments breed bacteria). Also, after surgery, you should avoid saunas until you’re cleared by your surgeon; the heat can increase swelling at the surgical site and you don’t want to risk infection or bleeding.
With skin conditions: something like eczema or psoriasis might actually improve with controlled heat and sweat for some people, but if you have an acute flare that’s very raw or you’re using medicated creams, check with your dermatologist. And definitely, if you have any infectious skin condition (like a fungal infection or impetigo), skip the public sauna for others’ safety and your own comfort.
7. Anyone Who Has Been Drinking Alcohol or Using Recreational Drugs: Alcohol and saunas are a dangerous mix
Alcohol increases the risk of dehydration, hypotension, and arrhythmias, and dulls your senses – you might not realize you’re overheating. Sadly, there are cases of people passing out or even dying in saunas when alcohol is involved.
The same goes for certain drugs (particularly stimulants like amphetamines or cocaine); these can raise heart rate and body temp on their own, and combined with a sauna can push you into heat stroke or cardiac issues. It is strongly advised to never use a sauna if you’re under the influence of substances.
8. Children and the Elderly (use caution)
Small children should not use saunas unless specifically cleared by a pediatrician and supervised closely. Children’s temperature regulation isn’t as developed, and they dehydrate faster. Many facilities have age limits (like no under 12, or something along those lines). If teens use it, they should be educated on proper use and time limits.
For elderly individuals, as mentioned, they can use saunas if healthy, but they often need shorter exposure and more caution because they may be more prone to blood pressure swings or dehydration. Some older adults with limited mobility also risk falls if they get lightheaded.
9. People on Certain Medications
If you take medications that affect how your body handles heat or water, be careful. For example:
- Diuretics (“water pills”) – these already make you lose fluid; combined with sauna sweating, you could get dehydrated or your blood pressure could drop too much.
- Beta blockers – these keep heart rate low; in a sauna, a normal response is to raise heart rate to cool you. Beta blockers might impair that, so your body might not handle the heat stress as well.
- Sedatives – these could make you too drowsy in the already relaxing heat, and risk of nodding off (not good to fall asleep in a sauna).
- Anticholinergics – they can prevent sweating; if you can’t sweat properly, you might overheat.
- Even some topical medicated patches (like a fentanyl pain patch or nicotine patch) can release faster with heat, leading to potential overdose. There was a case of a woman with fentanyl patches who died after sauna use due to increased absorption of the drug.
If you’re on any medication, it’s a good idea to ask your doctor if sauna use is safe. Often it is, but better to check.
10. People with certain Chronic Conditions
This is broad, but if you have very low blood pressure, kidney problems (which might make it hard to handle fluid shifts), severe adrenal gland issues, or uncontrolled diabetes (risk of neuropathy and not sensing heat, or dehydration issues), you should be cautious.
Also, individuals who cannot sweat normally (due to anhidrosis or ectodermal dysplasia, etc.) should avoid saunas because sweating is the main way the body cools in a sauna.
Final Thoughts
In short, avoid infrared sauna use if you are pregnant, have unstable heart or blood pressure conditions, are prone to overheating or fainting, or are under the influence of substances. Children should generally not use saunas (or only for very short times with lower heat and supervision). When in doubt, consult a healthcare provider before using a sauna, especially if you have chronic health issues.
The reasons underpinning these cautions come down to the sauna’s effects: it causes your body to heat up, blood vessels to dilate, heart rate to increase, and you to sweat out fluids. Any condition or situation that makes those changes risky (like an inability to compensate for lower blood pressure, or a fetus that can’t regulate heat, or an impaired cardiovascular system, etc.) means sauna use could be harmful.
Safety first – infrared saunas are wonderful for many, but not worth the risk if you fall into one of these categories unless you have clear medical guidance and precautions in place.
References:
American College of Obstetricians and Gynecologists (2021). Can I use a sauna or hot tub early in pregnancy? (ACOG advises against sauna use in pregnancy due to risk of birth defects from overheating).
Pacific Neuroscience Institute – Giesser, B. (2020). A Hot Topic: The Effects of Heat in Persons with Multiple Sclerosis. (Recommends MS patients avoid hot tubs and saunas because heat can temporarily worsen symptoms).
National Capital Poison Center – Johnson-Arbor, K. (2021). Are Saunas Good for You? (Warns that sauna use can result in dehydration, low blood pressure, and that people with certain conditions or on medication patches should avoid it).
