The sensation of feeling disoriented, lightheaded, or even “high” while sick is a common yet often perplexing experience for many individuals. This altered state of perception is not merely a figment of a feverish mind. There are underlying biological and neurological processes that contribute to this phenomenon.
The Body’s Biological Response
When the body encounters a pathogen, it mounts an immediate and complex immune response. This defense mechanism involves the activation of various immune cells that work to identify and eliminate the threat. A key part of this response is the release of signaling molecules known as cytokines. These small proteins act as messengers between immune cells, coordinating the body’s efforts to fight infection.
Some cytokines, such as interleukins, interferons, and tumor necrosis factor-alpha, are particularly important in this process. These molecules promote inflammation, a localized protective response that helps contain and eradicate pathogens. While inflammation is beneficial for fighting infection, these cytokines can also have systemic effects, influencing various bodily systems beyond the immediate site of infection. This systemic inflammation can lead to symptoms like fever, fatigue, and general malaise. The release of these inflammatory mediators is a coordinated effort to prioritize the body’s resources towards healing. The changes induced by these cytokines lay the groundwork for how illness impacts the brain.
Neurological Changes During Illness
The biological responses initiated by the immune system directly influence brain function, leading to the altered mental states experienced during illness. Cytokines and other inflammatory mediators can signal to the brain through several pathways. Some can cross the blood-brain barrier, a protective interface that typically restricts substances from entering the brain. Other cytokines may signal the brain via afferent nerve fibers or by activating cells within the brain itself.
Once in the brain, these inflammatory molecules affect various neurotransmitter systems, including dopamine and serotonin, which play roles in mood, motivation, and cognition. They can also impact brain regions involved in temperature regulation, contributing to fever. The collective changes in brain chemistry and activity manifest as what scientists refer to as “sickness behavior.” Sickness behavior is a set of adaptive behavioral changes that occur during illness, including lethargy, social withdrawal, reduced appetite, and altered perception. These changes are thought to conserve energy for the immune response and promote recovery.
Experiencing Altered States
The neurological changes brought on by illness can lead to a range of subjective experiences that contribute to feeling “high.” Individuals might experience lightheadedness, a sense of detachment, or disorientation. These sensations can be accompanied by unusual thoughts or a dream-like feeling, where reality seems less concrete.
Altered perception of time is also a common report, with minutes feeling like hours or vice versa. The brain’s processing of information can become less precise, leading to a sense of disinhibition or vivid, sometimes bizarre, dreams. These “fever dreams” are often more intense and negative than typical dreams, reflecting the brain’s altered state due to elevated temperature and inflammatory signals.
When to Seek Medical Guidance
While feeling “high” during an illness can be a common side effect of the body’s immune response, certain symptoms warrant medical attention. It is important to distinguish between typical sickness sensations and signs of a more serious condition. For instance, severe confusion, persistent disorientation, or hallucinations that do not resolve quickly should prompt a medical evaluation.
Other red flags include extreme lethargy, difficulty breathing, or a high fever that remains elevated despite home care or exceeds 103°F (39.4°C) in adults. If symptoms worsen rapidly, or if there is a stiff neck, severe headache, or a rash accompanying the fever, seeking prompt medical advice is important. These signs could indicate a complication or a more severe underlying infection requiring professional intervention.