Why You Shouldn’t Drink Alcohol Before a Sauna Session

Don’t drink alcohol before a sauna session. Alcohol and heat both widen your blood vessels, and in the one study that measured the combination, systolic blood pressure fell by an average of about 23 mmHg in a traditional Finnish sauna after heavy drinking — while the same men’s blood pressure held steady in the sauna without alcohol. Fainting in a hot, enclosed room, often alone, is the hazard the evidence actually documents, and alcohol also dulls the judgement you need to notice trouble coming. Contrary to a popular myth, you cannot "sweat out" alcohol: under 10% of it leaves the body unchanged in breath, sweat and urine combined, and around 90% is broken down by the liver.

Key Takeaways

• Drinking alcohol before using an indoor or outdoor infrared sauna can drop your blood pressure sharply — the measured average fall in one study was about 23 mmHg — which is why fainting, not a heart-rhythm problem, is the documented risk.
• Deaths in a sauna are rare — under 2 per 100,000 people a year in Finland — but half of the people in that country’s forensic record of sauna deaths were under the influence of alcohol.
• Home sauna wellness sessions are best enjoyed hydrated and alert.
• The myth that you can “sweat out” alcohol in a luxury home sauna is false; alcohol is mainly metabolized by the liver, not eliminated through sweat.
• Skip alcohol before and during sauna sessions so you can enjoy the heat while alert and hydrated.

A problematic and potentially dangerous practice has emerged amid the rising trend of integrating saunas into social gatherings. Some sauna users are drinking alcohol before their sauna session. While sipping a drink might feel like a way to enhance relaxation, alcohol and saunas are a risky combination.

Understanding why alcohol should not precede a sauna session is a straightforward way to protect your health and get more out of the session itself. Read on to understand why you should avoid alcohol before and during your sauna session.

What Happens To Your Body During Sauna Exposure?

When you enter an outdoor infrared sauna or a red light sauna, your body works to regulate its core temperature. Blood vessels dilate, heart rate increases, and sweat glands activate, cooling your system through perspiration.

This produces a cardiovascular effect broadly similar to moderate exercise, with your heart pumping faster and more blood circulating to the skin. People commonly report improved circulation, better-looking skin, and relief from joint and muscle stiffness. But all of this places a real demand on the body.

Tip: To get the most from home sauna wellness, hydrate thoroughly before entering any sauna session and avoid substances that can disrupt your body's cooling functions. To learn more about this: Sauna Hydration: Stay Safe & Prevent Dehydration

Your body loses fluid through sweat, and the cardiovascular system is under load. If you are healthy and hydrated, that is generally well tolerated. Add alcohol, however, and the body's carefully balanced mechanisms are disrupted in ways that can have serious consequences.

Physiological Impact of Sauna Use: Hydrated vs. Alcohol-Impaired

A comparison of how the body manages heat stress when sober versus when alcohol is present in the bloodstream.

What is Alcohol’s Impact on the Body?

Alcohol is a central nervous system depressant. Its most immediate and noticeable effects are reduced inhibitions, a sense of euphoria, and relaxation. That might seem like a perfect precursor to a calming sauna session, but the perception is misleading.

Alcohol acts on the hypothalamus, which governs temperature control, and it causes vasodilation — the blood vessels near your skin open up, exactly as they do in the heat. How far that actually disrupts heat tolerance is less settled than the popular advice suggests. A 2024 systematic scoping review of alcohol and human responses to heat stress pooled eight studies of 93 participants, all male, and found that the usual markers of dehydration were not consistently observed; its authors concluded that, contrary to current heat-health advice, alcohol did not appear to impair physiological responses to heat in young healthy men (Morris et al., Environmental Health, 2024). The hazard that is documented is what the combination does to your blood pressure, and that is covered in the sections below.

Alcohol is also a diuretic. It suppresses vasopressin, the hormone that tells your kidneys to hold on to water — in one study, plasma vasopressin fell within 30 minutes of drinking and the men lost most of a kilogram of water over two hours (Leppäluoto et al., 1992, PMID 1533484) — so it works against you at exactly the moment a sauna is increasing fluid loss through sweat. Dehydration impairs muscle coordination, disrupts judgment and lowers blood pressure, and every one of those matters more in a hot room than out of one.

Tip: The infrared sauna health benefits you are after are easiest to notice when you are well hydrated and paying attention to your body's signals.

Why Is It Dangerous To Drink Alcohol Before Using A Sauna?

Dehydration and Heat Stroke

Dehydration is the risk most people name first. Beyond thirst and dry skin, dehydration can lead to dizziness, confusion, fainting and heat stroke.

When your body is short of fluid, it cannot sweat effectively — and sweating is your primary cooling method in the sauna. The Mayo Clinic describes heat stroke as a medical emergency that occurs when body temperature rises too quickly and the cooling mechanisms fail, and notes that it can damage organs and can be fatal if it is not treated.

Early symptoms are easy to miss, especially when alcohol dulls your senses. It is also worth noting that several signs of heat stroke — dizziness, confusion, nausea — overlap with signs of alcohol intoxication. That overlap can delay recognition and delay help.

Tip: Even in the best indoor or outdoor infrared sauna environments, don't mix alcohol with deep heat exposure. Learn more about sauna safety: Sauna & Cold Plunge: Key Health Benefits and Safety Tips

Blood Pressure, Fainting and Sudden Collapse

A second, less obvious risk is the load you place on your cardiovascular system when you use a sauna after drinking. The best infrared sauna for home naturally raises your heart rate, in a way broadly comparable to light or moderate exercise for a healthy person.

This is the part of the combination that has actually been measured. A 1992 study in the Journal of Internal Medicine put 10 healthy men through a traditional Finnish sauna with and without heavy drinking. The sauna alone left systolic blood pressure at baseline; sauna plus alcohol dropped it markedly, from an average of 136 to 113 mmHg — a fall of roughly 23 mmHg (Roine et al., PMID 1588256). Heart rate rose by a comparable amount either way.

Two things follow from that, and both matter. The documented hazard is low blood pressure and fainting rather than a heart-rhythm problem: the same study looked for extra premature ventricular beats and did not find them, concluding that a sauna, even combined with heavy drinking, did not appear to provoke arrhythmias in healthy young men. And the setting was a traditional Finnish sauna, not an infrared cabin of the kind we build, which runs at 110–170°F.

For someone who has consumed alcohol, the load is compounded. Alcohol causes vasodilation and lowers blood pressure. While that might sound harmless, in a high-heat environment it can mean less blood reaching vital organs. The result can be a sudden drop in blood pressure that may cause fainting or loss of consciousness — a particular concern if you are in a private sauna or unattended.

Passing out in a sauna means prolonged, unmonitored heat exposure, which is exactly the situation the Mayo Clinic's heat-stroke guidance is written about. Heat and alcohol both widen your blood vessels, so their effects can stack rather than cancel out, and blood pressure may fall further in a sauna than it would from either one alone. Blood pools in the extremities, which reduces the supply reaching the brain — the mechanism behind lightheadedness, dizziness and fainting in a sauna, and the reason we tell customers not to mix the two.

What the Forensic Record Shows

Deaths in a sauna are rare. In Finland — the country with the highest sauna use in the world — police and forensic records from 1990 to 2002 put the rate at under 2 per 100,000 inhabitants a year. When a death does happen, heat exposure is the cause in about a quarter of cases, and half of everyone who died was under the influence of alcohol (Kenttämies and Karkola, Journal of Forensic Sciences, 2008, PMID 18471223). Two caveats travel with that figure: these are traditional Finnish saunas, not infrared cabins, and this is autopsy data, so it shows alcohol present in half of sauna deaths rather than proving alcohol caused them. The researchers' own conclusion on prevention was that people should drink less before a sauna.

Impaired Judgment

Alcohol dulls your cognitive senses, making it harder to recognize when you are becoming dehydrated, overheating, or approaching your limits. It reduces your ability to make rational decisions, such as knowing when to seek help or step out of the sauna.

The best sauna for home asks for awareness of your body's signals — lightheadedness, unusual fatigue, dizziness — so you can take a break or rehydrate. With alcohol clouding your mind, you may overlook those warning signs. It also raises the likelihood of ordinary accidents, like misusing sauna equipment or slipping on a wet floor.

The Social Pressure Factor and Normalization of Risk

Alcohol and saunas have been culturally linked, especially in countries like Finland, where both are woven into social life. In some settings, sharing beers or shots before or after a sauna session is unremarkable. That normalization can mask the risk, and peer pressure plays a role too — people may go along with the group even when they know better.

What starts as a relaxing evening can become a medical emergency, especially if nobody in the group recognizes the signs of heat exhaustion or dehydration. Prevention is far easier than intervention. Deciding for yourself to skip alcohol before a sauna can influence the people around you to do the same, and help keep everyone safe.

Pro Tip: Flip the order of your evening. Make the sauna the opening activity and drinks the after-party, so heat exposure always happens while everyone is sober and alert.

Can You Actually Sweat Out Alcohol In A Sauna?

A persistent myth behind this risky behaviour is the belief that you can sweat out alcohol in the best outdoor sauna. Sweating does move some substances out through the skin, but alcohol is mainly metabolized by the liver: less than 10% of the alcohol you drink leaves the body unchanged in breath, sweat and urine combined, while around 90% is broken down by oxidation, most of it in the liver (Cederbaum, Clinics in Liver Disease, 2012).

The amount you can expel through sweat is negligible next to what remains in your bloodstream. Using a sauna to speed up sobering only adds heat stress to a system already dealing with alcohol. Rather than clearing alcohol faster, you may increase your chances of disorientation and dehydration.

The idea that a sauna session will make you less drunk, or work as a hangover cure, is false and dangerous. It can create a misleading sense of sobriety that leads to poor decisions, like driving or continuing to drink.

Alternatives for Sauna Wellness

If social connection and relaxation are what you are looking for, there are safer ways to enjoy a sauna. Hydrate well before your session with water or an electrolyte drink. Eat a light meal beforehand to steady blood sugar, and keep sessions to around 15–20 minutes at a time, or whatever your sauna's own guidance recommends.

These are general guidelines, not medical advice. If you have a health condition, are pregnant, or take medication, talk to your healthcare provider about what is appropriate for you.

Tip: An optimal home sauna wellness routine is built on preventative habits. Hydrate, eat lightly, and share the experience responsibly so you can get the most from the session.

If you are in a social setting, save the alcohol for after the sauna session, and rehydrate thoroughly before you have any. You will get more out of the session if you are alert, hydrated, and able to notice how you feel.

Many people report clearer-looking skin, better sleep, and improved mood after a sauna. Whatever you get out of a session, you are more likely to notice it when your body is not also processing alcohol.

Quick facts About Alcohol and Sauna You Need to Know

• Blood Pressure: In the one study that measured it, heavy drinking before a traditional Finnish sauna dropped systolic blood pressure by an average of about 23 mmHg — from 136 to 113 — in 10 healthy men, while the same men’s blood pressure held steady in a sauna without alcohol (Roine et al., Journal of Internal Medicine, 1992, PMID 1588256).
• Metabolic Reality: Sweating is not a meaningful route of alcohol elimination — under 10% of the alcohol you drink leaves the body unchanged in breath, sweat and urine combined, while around 90% is broken down by oxidation, mostly in the liver (Cederbaum, Clinics in Liver Disease, 2012).
• Dehydration: Alcohol suppresses vasopressin, the hormone that tells the kidneys to hold on to water; in one study plasma vasopressin fell within 30 minutes of drinking and the men lost most of a kilogram of water over two hours (Leppäluoto et al., 1992, PMID 1533484) — working against you at exactly the moment a sauna session is increasing fluid loss through sweat.
• How Often It Goes Wrong: Sauna deaths in Finland run at under 2 per 100,000 people a year; heat exposure is the cause in about a quarter of them, and half of the people who died had been drinking (Kenttämies and Karkola, Journal of Forensic Sciences, 2008).

Finally

Drinking alcohol before your sauna session is not a good idea, however indulgent it sounds in a social setting. The risks outweigh the momentary pleasure. Between a sharp fall in blood pressure, dehydration, impaired judgment and heat you can no longer judge, the combination can quickly turn deadly — the Mayo Clinic classes heat stroke as a medical emergency.

A sauna should be a place for health and recovery, not risky behaviour. Approach sauna use with care, educate the people around you, and speak up if you see someone drinking before or during a session.

Sun Home Saunas makes infrared saunas, the popular infrared sauna blanket, and home cold plunge tub setups.

Reach out today and connect with our sauna experts to bring the full benefits of sauna therapy into your daily life.

References

1. Cederbaum A. I. (2012). Alcohol metabolism. Clinics in Liver Disease, 16(4), 667–685. https://doi.org/10.1016/j.cld.2012.08.002
2. Cleveland Clinic. (2023, June 5). Dehydration. Cleveland Clinic. https://my.clevelandclinic.org/health/diseases/9013-dehydration
3. Kenttämies, A., & Karkola, K. (2008). Death in sauna. Journal of Forensic Sciences, 53(3), 724–729. https://doi.org/10.1111/j.1556-4029.2008.00703.x
4. Leppäluoto, J., Vuolteenaho, O., Arjamaa, O., & Ruskoaho, H. (1992). Plasma immunoreactive atrial natriuretic peptide and vasopressin after ethanol intake in man. Acta Physiologica Scandinavica, 144(2), 121–127. https://doi.org/10.1111/j.1748-1716.1992.tb09276.x
5. Mayo Clinic. (2022, June 25). Heatstroke - Symptoms and causes. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/heat-stroke/symptoms-causes/syc-20353581
6. Morris, N. B., Ravanelli, N., & Chaseling, G. K. (2024). The effect of alcohol consumption on human physiological and perceptual responses to heat stress: a systematic scoping review. Environmental Health: A Global Access Science Source, 23(1), 73. https://doi.org/10.1186/s12940-024-01113-y
7. Roine, R., Luurila, O. J., Suokas, A., Heikkonen, E., Koskinen, P., Ylikahri, R., Toivonen, L., Härkönen, M., & Salaspuro, M. (1992). Alcohol and sauna bathing: effects on cardiac rhythm, blood pressure, and serum electrolyte and cortisol concentrations. Journal of Internal Medicine, 231(4), 333–338. https://doi.org/10.1111/j.1365-2796.1992.tb00941.x