Hot flashes and flushing episodes are a real and documented feature of COVID-19, showing up both during acute illness and, more persistently, as part of long COVID. In post-COVID clinics in England, roughly six in ten patients reported hot flushes regardless of age, including younger adults in their twenties and thirties who would not normally experience them. The causes appear to involve a tangle of mechanisms, from disrupted thermoregulation in the brain to immune system overactivity, and the experience can look different depending on your age, sex, and hormonal status.
How Common Are Hot Flashes After COVID
Data from three post-COVID syndrome clinics in England found that hot flushes affected about 62% of patients overall. What caught researchers off guard was that even the youngest group, those aged 18 to 39, reported hot flushes at nearly the same rate as older patients, around 61%. Night sweats were similarly common at about 64% across the full cohort. These numbers fall within the range seen in observational studies of menopausal women, but the fact that young people reported them at comparable rates points to something beyond normal hormonal aging.1IJID Regions. Menopause symptom prevalence in three post–COVID-19 syndrome clinics in England: A cross-sectional analysis
A separate study of perimenopausal women who had recovered from COVID-19 reported even higher numbers. Among 52 women surveyed, about 83% experienced hot flashes, and nearly half of them said their hot flashes started only after their COVID infection, meaning they had no history of the symptom beforehand.2Russian Journal of Woman and Child Health. Perimenopausal disorders in women after COVID-19 That figure is striking because it suggests the virus itself can trigger vasomotor symptoms in women who were not yet experiencing them as part of their natural menopausal transition.
Why COVID Can Disrupt Your Internal Thermostat
Your body’s temperature control center sits in the hypothalamus, a small region deep in the brain that also regulates hormones, sleep, and stress responses. SARS-CoV-2 can potentially reach the hypothalamus, and researchers have focused on this pathway as a key route for the neurological symptoms that crop up during and after infection.3PubMed Central. COVID-19 and Neurological Impairment: Hypothalamic Circuits and Beyond When the hypothalamus or the nerve circuits it communicates with are thrown off, the body can misread its own temperature, triggering sudden heat surges and sweating episodes even when you are not actually overheating.
In long COVID specifically, researchers have found measurable evidence that the autonomic nervous system, the involuntary wiring that controls heart rate, blood vessel dilation, and sweating, behaves abnormally. A study comparing long COVID patients with healthy controls found that those within the first four months after infection showed reduced heart-rate variability, a marker of autonomic imbalance. The same group had elevated levels of inflammatory molecules called IL-17 and IL-2, suggesting that lingering inflammation was actively interfering with autonomic nerve function.4PubMed Central. Imbalance of Peripheral Temperature, Sympathovagal, and Cytokine Profile in Long COVID The practical consequence is that the signals telling your blood vessels to dilate and your sweat glands to activate can fire at the wrong times, producing the familiar rush of heat, redness, and perspiration.
During the acute phase of severe COVID, the immune system can release a flood of inflammatory signaling molecules, sometimes called a cytokine storm. Patients with active infections have been found to carry high levels of several of these molecules, including IL-1, IL-6, TNF-α, and others, some of which track with how sick the person becomes.5PubMed Central. Cytokine Storm in COVID-19: Immunopathogenesis and Therapy Some of these same molecules are known to act on the hypothalamus and directly alter the body’s temperature set point. So while fever is the most obvious thermal symptom of acute COVID, episodic flushing and heat intolerance fit the same biological picture of immune-driven thermoregulatory disruption.
The Hormonal Connection
For women in particular, COVID appears to interact with the hormonal axis in ways that amplify or trigger menopausal-type symptoms. Clinicians working in long COVID clinics have observed that many women report worsening hot flushes and night sweats after infection, alongside menstrual cycle changes. There is a plausible biological explanation for this overlap: the ACE2 receptor, which SARS-CoV-2 uses to enter cells, is expressed in tissues throughout the reproductive system and in the brain regions that regulate sex hormones and body temperature.6PubMed Central. Long COVID risk – a signal to address sex hormones and women’s health
Research on long COVID’s effects on female reproductive health has documented hormonal imbalances contributing to menstrual irregularities and impaired ovarian function.7PubMed Central. Clinical Spectrum of Long COVID: Effects on Female Reproductive Health If the virus or the immune response it provokes disrupts estrogen production, even temporarily, the thermoregulatory circuits that depend on estrogen signaling become more sensitive. That is exactly the mechanism behind hot flashes during natural menopause, and it may explain why some younger women develop vasomotor symptoms for the first time after COVID.
Interestingly, menopausal status seems to affect how symptomatic a woman becomes during acute infection. A study of women over 45 found that those in premenopause or perimenopause were significantly more likely to experience COVID symptoms overall compared with postmenopausal women. Fatigue, muscle aches, and loss of smell were all more common in the premenopausal and perimenopausal group, with adjusted odds roughly three to six times higher for these symptoms.8PubMed Central. Being in postmenopause may be associated with lower prevalence of COVID-19 symptoms among women over 45 years of age with and without HIV This does not mean postmenopausal women are protected from hot flashes after COVID, but it does suggest that hormonal fluctuations during the perimenopausal window may heighten overall symptom intensity.
Night Sweats as a Long COVID Symptom
Night sweats deserve special mention because they are among the most disruptive and underrecognized aftereffects of COVID. Estimates suggest that up to a quarter of people with long COVID deal with persistent nighttime sweating, yet the symptom often goes unaddressed by clinicians until it resolves on its own.9F1000Research. Impact of evening carbohydrate intake on the resolution of persistent night sweats in patients with long COVID: a case series For the person waking up drenched at 3 a.m. multiple nights a week, that is a significant quality-of-life problem, one that compounds the fatigue and cognitive fog already common in long COVID.
One hypothesis ties post-COVID night sweats to disrupted glucose metabolism. SARS-CoV-2 is known to interfere with how the body handles blood sugar, and some researchers have proposed that impaired energy production at the cellular level leads to faster overnight depletion of glycogen stores. When the body senses falling blood sugar during sleep, it releases adrenaline to mobilize energy, and adrenaline triggers sweating. A small case series tested this idea by having three non-diabetic long COVID patients eat a carbohydrate-rich snack before bed. After one week, all three reported that their night sweats had completely stopped.9F1000Research. Impact of evening carbohydrate intake on the resolution of persistent night sweats in patients with long COVID: a case series The study was tiny and preliminary, but the logic is sound enough that a bedtime snack is a low-risk, low-cost thing to try if persistent night sweats are bothering you after COVID.
Mast Cells and Flushing
Not all post-COVID hot flashes follow the same biological path. Some researchers have traced the flushing episodes to mast cells, a type of immune cell that releases histamine and other inflammatory chemicals. In long COVID, there is growing evidence that mast cells become abnormally activated, releasing excessive amounts of these chemicals in a pattern that resembles a condition called mast cell activation syndrome.10PubMed Central. Immunological dysfunction and mast cell activation syndrome in long COVID
A study comparing flushing severity across groups found that long COVID patients scored significantly higher than healthy controls. Specifically, the average flushing severity score was about 0.6 in controls and jumped to 2.2 in people with post-COVID long symptoms. People with an established diagnosis of mast cell activation syndrome scored even higher at 3.8, but the long COVID group clearly sat between healthy and full-blown mast cell disease.11International Journal of Infectious Diseases. Mast cell activation symptoms are prevalent in Long-COVID This matters practically because mast-cell-driven flushing can respond to antihistamines and related medications, which gives clinicians a treatment angle they might not consider if they assume the flushing is purely hormonal or neurological.
Thyroid Inflammation After COVID
There is another less obvious source of post-COVID heat intolerance that gets mistaken for hot flashes: thyroid inflammation. A systematic review of subacute thyroiditis after COVID-19 found that patients commonly reported symptoms including heat intolerance, palpitations, tremors, neck pain, unintentional weight loss, and fatigue.12PubMed Central. Subacute thyroiditis as a post-COVID-19 complication: a systematic review Subacute thyroiditis causes the thyroid gland to dump stored hormones into the bloodstream, temporarily pushing you into a hyperthyroid state. That excess thyroid hormone speeds up metabolism and makes you feel overheated, flushed, and sweaty.
The distinction matters because thyroid-driven heat intolerance has a different trajectory and treatment from the autonomic or hormonal hot flashes described earlier. It typically shows up weeks to months after the initial infection, can be confirmed with a simple blood test, and usually resolves on its own or with short-term anti-inflammatory treatment. If you are experiencing persistent feelings of being overheated after COVID alongside a rapid heartbeat, trembling hands, or unexpected weight loss, it is worth asking your doctor to check your thyroid levels rather than assuming the problem is menopausal or neurological.
Managing Post-COVID Hot Flashes
Treatment for post-COVID vasomotor symptoms depends heavily on the suspected underlying cause, and unfortunately there is no single large trial that tested a one-size-fits-all approach. A scoping review of treatments for long COVID autonomic dysfunction, which includes the thermoregulatory problems that drive many hot flashes, identified several regimens that have been tried in small studies. These ranged from antihistamine combinations and heart-rate variability biofeedback to nutraceutical formulations and compression garments. Clinical guidelines for long COVID autonomic issues generally recommend starting with lifestyle measures like adequate hydration, salt intake, and graduated exercise.13SpringerLink. Treatments for Long COVID autonomic dysfunction: a scoping review
For women whose hot flashes appear driven by hormonal disruption, clinicians in long COVID settings have discussed the potential role of hormone replacement therapy, particularly when the vasomotor symptoms overlap with other perimenopausal changes worsened by infection.6PubMed Central. Long COVID risk – a signal to address sex hormones and women’s health This is not yet supported by randomized trial data specific to post-COVID patients, so it remains a clinical judgment call rather than a guideline recommendation. If mast cell activation is suspected, the flushing component may respond to over-the-counter antihistamines, which some long COVID patients report finding helpful for a range of symptoms beyond just flushing.
One case report documented a patient whose post-COVID hot flashes were severe enough to require hospitalization. Using traditional Korean medicine treatment, the patient’s hot flash diary score dropped from 24 to zero within eight days, and the improvement persisted after discharge.14The Journal of Internal Korean Medicine. Korean Medicine Treatment for a Patient Complaining of Hot Flashes after COVID-19 Infection That is a single case and says nothing definitive about broader treatment strategies, but it does illustrate two things: post-COVID hot flashes can be severe enough to seriously impair daily life, and they can resolve relatively quickly with treatment once someone takes them seriously.
Who Gets Hit Hardest and Who Gets Missed
The demographics of post-COVID hot flashes create a visibility problem. Because hot flashes are culturally associated with menopause, younger women and men who develop them after COVID may not mention the symptom to their doctors, or may have it dismissed. The clinic data from England showing that people in their twenties and thirties reported flushing at rates comparable to older patients should put this assumption to rest.1IJID Regions. Menopause symptom prevalence in three post–COVID-19 syndrome clinics in England: A cross-sectional analysis The symptom is not age-restricted, and treating it as “just menopause” in an older patient or as “impossible” in a younger one both lead to missed diagnoses.
Men get less attention in the literature on this topic, partly because the research has leaned heavily toward female reproductive health impacts. But the autonomic dysfunction and mast cell activation pathways described earlier are not sex-specific. The autonomic nervous system disruption that produces flushing and temperature instability affects anyone whose nervous system was hit hard by the virus, regardless of hormonal status. If you are male and experiencing unexplained episodes of flushing, sweating, and heat intolerance after a COVID infection, the same underlying mechanisms apply and the same conversations with your doctor are worth having.
When Post-COVID Flushing Overlaps With Other Conditions
One of the trickier aspects of post-COVID hot flashes is that they can look identical to symptoms of conditions that existed before infection or that develop independently. Perimenopausal women who contract COVID face a genuine diagnostic puzzle: did the virus worsen their existing transition, or would these symptoms have arrived on schedule regardless? The data showing that nearly half of perimenopausal women in one study traced their hot flashes to after their COVID infection suggests the virus played a triggering role, but disentangling the two causes in any individual person is difficult.2Russian Journal of Woman and Child Health. Perimenopausal disorders in women after COVID-19
Anxiety and panic disorders, which have surged during and after the pandemic, also produce episodes of flushing, heat, and sweating that mimic vasomotor hot flashes. So do certain medications, including some antidepressants that people may have started during the pandemic period. The pattern of the episodes can help sort things out: classic menopausal hot flashes tend to rise in waves and last a few minutes, autonomic dysfunction flushes may be triggered by postural changes or exertion, mast-cell flushing often comes with additional symptoms like itching or gastrointestinal upset, and thyroid-related overheating is usually more constant rather than episodic. None of these patterns are perfectly reliable on their own, but together with bloodwork and a careful history, they can point toward the right explanation and, more importantly, the right treatment.