Excessive sweating is a commonly reported symptom of COVID-19 infection. Changes in the body’s temperature regulation have been noted, ranging from intense episodes during the acute illness to persistent issues months after recovery. Understanding this connection requires looking at how the body’s defense mechanisms interact with the virus. This article clarifies the physiological reasons behind this symptom and what it may signal regarding one’s health status.
Acute Sweating: Fever and the Immune Response
The most immediate cause of excessive sweating during an active COVID-19 infection is the body’s fever response. When the immune system detects a pathogen, it releases signaling molecules called cytokines. These molecules prompt the hypothalamus in the brain to raise the body’s core temperature set point, deliberately creating an inhospitable environment for the virus.
Sweating is the natural process the body uses to counteract overheating once the fever has peaked or begins to decline. As the core temperature set point is lowered, the body releases sweat onto the skin. The evaporation of this sweat cools the body down, helping it return to a safer temperature range.
This mechanism often causes “night sweats,” where a person wakes up drenched. Night sweats occur because the immune system is highly active during sleep, leading to fluctuations in body temperature as the fever breaks. These intense episodes can be disruptive and may even precede the onset of a full fever.
Persistent Sweating and Long COVID
For some people, excessive sweating, or hyperhidrosis, continues long after the acute infection has passed, becoming a symptom of Long COVID. This persistent sweating is distinct because it occurs without an active fever and is often related to dysautonomia. Dysautonomia refers to disorders affecting the autonomic nervous system (ANS), which controls involuntary functions like heart rate, blood pressure, and temperature regulation.
The viral infection may trigger an altered immune response that results in the dysregulation of the ANS. This dysregulation can lead to an overstimulation of the sympathetic nervous system, the “fight or flight” component. When the sympathetic system is in overdrive, it can cause inappropriate or exaggerated sweating episodes, even when the body is not hot.
Excessive sweating is one of many symptoms linked to post-COVID dysautonomia, alongside chronic fatigue, heart palpitations, and brain fog. This autonomic dysfunction can manifest as part of conditions like Postural Orthostatic Tachycardia Syndrome (POTS). This persistent symptom indicates that the body’s automatic control systems are struggling to maintain balance following the viral assault.
When Sweating Requires Medical Attention
While sweating is a normal response to fever, certain accompanying symptoms warrant immediate medical evaluation. Seek urgent medical attention if excessive sweating is paired with chest pain, lightheadedness, or nausea, as these may signal a serious complication.
Contact a healthcare provider if the sweating suddenly increases dramatically or if it disrupts daily life. Any instance of persistent, drenching night sweats should be evaluated to rule out other underlying medical conditions, such as infections or endocrine issues.
Persistent symptoms, including excessive sweating, that last for more than four weeks after the initial infection should prompt a conversation with a doctor about potential Long COVID or dysautonomia. Medical professionals can perform tests to determine the cause of the hyperhidrosis and develop an appropriate management plan.