Does Long COVID Lead To Alcohol Intolerance?

One of the biggest challenges the world has been left to grapple with in the wake of the coronavirus (COVID-19) pandemic is what’s being referred to as “long COVID.”

That is, new, ongoing, or returning symptoms of COVID-19 (or other forms of illness) that persist beyond four weeks of contracting the illness.

This condition, also known as a “long hauler” or post-acute COVID-19 syndrome, may be identified by certain physical and mental symptoms.

According to the United Kingdom’s ME Association, one of those symptoms may be a reduced tolerance for alcohol or symptoms of alcohol intolerance.

As of 2024, an estimated 17 million American adults are currently living with long COVID, according to data from the CDC and the Kaiser Family Foundation. Roughly 7 percent of all U.S. adults report having had long COVID at some point.

Post-Acute COVID And Alcohol Intolerance

Many people have shared anecdotal accounts of experiencing a reduced tolerance for alcohol after contracting the COVID-19 infection.

For instance, some symptoms reported by self-described “long-haulers” include:

• reduced tolerance for alcohol
• feeling sick after just a few sips of alcohol
• poor mental health for days after drinking alcohol
• increased anxiety after drinking alcoholic beverages
• signs of heightened alcohol sensitivity (e.g., rash, flushing, redness)
• signs of alcohol intolerance (e.g., warm flushing, severe hangover symptoms, rapid heart rate)
• worsened symptoms of long COVID-19

Does COVID-19 Reduce Alcohol Tolerance?

At this point in time, it is unclear whether the virus itself reduces your tolerance for alcohol. It’s possible for other factors to come into play.

Factors that may affect your alcohol tolerance after COVID-19:

• reducing/stopping your alcohol use while sick
• drinking less often/not at all
• other physical or mental health conditions
• lingering symptoms of COVID-19 (e.g. chronic fatigue)

Research shows that many people during the pandemic either notably increased their alcohol intake during COVID-19, or did the opposite: embraced sobriety.

At the height of the pandemic, nearly 25 percent of Americans reported using alcohol to help manage pandemic-related stress, according to a 2021 survey from the American Psychological Association.

At the same time, many adults have also reported deciding to go dry, or eliminating alcohol completely — opting instead of non-alcoholic alternatives, such as non-alcoholic seltzer, or faux beer.

Does COVID-19 Cause Alcohol Intolerance?

Alcohol intolerance is a genetic, metabolic condition.

Research on the long-term effects of COVID-19 remains ongoing. While a definitive causal link has not been established, a 2023 peer-reviewed case series from Stanford University’s Post-Acute COVID-19 Syndrome (PACS) Clinic documented four patients who developed new-onset alcohol sensitivity following COVID-19 infection.

Researchers proposed several potential mechanisms, including disruption of the gut microbiome, orthostatic intolerance (reduced blood flow when upright), and COVID-related inflammation affecting the blood-brain barrier. Larger studies are still needed.

What Is Alcohol Intolerance?

Alcohol intolerance, as it’s conventionally understood, is a genetic mutation that affects your body’s ability to convert acetaldehyde to acetic acid.

Acetaldehyde is a toxic substance that comes from ethanol, which is in alcohol. When you drink, enzymes in your body will convert that ethanol into acetaldehyde.

From there, an enzyme known as aldehyde dehydrogenase 2 will help convert that toxic chemical compound into acetic acid, which is non-toxic.

Alcohol intolerance, however, is associated with inactive or less active ALDH2 — thereby thwarting that process of conversion.

Signs and symptoms of alcohol intolerance can include:

• warm flushing (e.g. facial redness)
• runny or stuffy nose
• nausea or vomiting
• hives
• hypotension (low blood pressure)
• diarrhea
• severe hangover symptoms
• rapid heart rate or palpitations
• worsened asthma

Alcohol Use Disorder And COVID-19

Alcohol use disorder became a growing problem for many over the course of the COVID-19 pandemic and the lockdown early on.

Increased loneliness, isolation, stress, and other common risk factors for alcohol use disorder have led some to heavy drinking as a form of self-medication.

Rates of relapse among those in recovery from alcohol use disorder have also reportedly increased, due to similar risk factors, as well as challenges accessing treatment.

Changes in drinking behavior, either drinking more or less than usual, can affect your alcohol tolerance, as well as the impact of alcohol on your life.

Alcohol use disorder has been associated with:

• risk of certain cancers
• liver damage/disease
• alcohol dependence and addiction
• insomnia
• poor mental health (e.g. anxiety, depression)
• difficulties at work, school, and in relationships
• weakened immune system response
• learning and memory problems

Getting Help For Alcohol Use Disorder

Early on in the pandemic, many people with mental health and substance use disorders were either cut off from treatment, or faced barriers to health care.

As of 2025, there are no validated, widely approved treatments specifically for long COVID itself. Management is focused on individual symptom relief, including mental health support, and people with long COVID are encouraged to work closely with their care team.

For people who didn’t have prior issues with alcohol, the same issues also emerged: difficulties finding or accessing professional treatment.

Now, it’s becoming easier for some people to find treatment services, although unrelated barriers — such as cost barriers — may still persist.

Treatment for alcohol use disorder will often involve:

• alcohol detoxification (detox)
• behavioral therapy
• substance use counseling
• group therapy and support groups
• mental health treatment (or dual diagnosis)
• relapse prevention planning

Alcohol use disorder treatment may be best delivered through an inpatient, residential, or outpatient rehab program, depending on the severity of the problem and other personal factors.

If you or a loved one with post-acute COVID-19 is facing a drinking problem, call our helpline to find the best available treatment options today.

Written by the Addiction Resource Editorial Staff