While the allergic reaction itself does not directly add sugar to the bloodstream, there is a recognized physiological connection. Allergies trigger a cascade of internal responses that mimic a physical stress event, and this stress reaction can directly disrupt the body’s ability to manage glucose effectively. This systemic disruption can lead to noticeable spikes in blood sugar levels, presenting a challenge for individuals focused on metabolic control.
The Body’s Stress Response to Allergens
The immune system interprets an allergic reaction as a physical threat, even though it is a sensitivity to an otherwise harmless substance. This immediate activation launches a systemic inflammatory response. The body perceives this inflammation as a stressor, triggering the release of stress hormones like cortisol and epinephrine.
These hormones are designed to prepare the body for “fight or flight” by ensuring a rapid supply of energy. Cortisol stimulates the liver to produce and release stored glucose into the bloodstream, a process called gluconeogenesis. Epinephrine, also known as adrenaline, works alongside cortisol to increase this glucose output from the liver.
Simultaneously, these stress hormones induce a state of temporary insulin resistance in muscle and fat cells. This means the body’s cells become less responsive to insulin, the hormone responsible for moving glucose out of the blood and into the cells. The resulting combination of increased glucose production and decreased glucose uptake causes a spike in circulating blood sugar.
Common Allergy Medications and Glucose Levels
Beyond the body’s natural reaction, certain medications used to treat severe allergy symptoms can independently raise blood sugar. Systemic corticosteroids, often prescribed in oral or injectable form for severe allergic reactions or asthma flares, are the primary concern. These anti-inflammatory drugs directly block the action of insulin and promote glucose production.
Corticosteroids can cause a significant increase in blood glucose, sometimes leading to steroid-induced hyperglycemia or, in rare cases, steroid-induced diabetes. The effect is dose-dependent, meaning higher doses or longer courses lead to more pronounced spikes. In contrast, inhaled or nasal spray corticosteroids have minimal absorption into the bloodstream, but monitoring is still warranted for sensitive individuals.
Another class of medication that can affect glucose control is oral decongestants, such as those containing pseudoephedrine. These drugs are sympathomimetic agents, meaning they chemically mimic the effects of the body’s stress hormones, epinephrine and norepinephrine. By activating the nervous system, they can cause an increase in heart rate, blood pressure, and blood sugar levels. Individuals managing diabetes should approach these over-the-counter decongestants with caution and consult a healthcare provider before use.
Monitoring and Management During Allergy Season
For those managing blood sugar, it is helpful to treat severe allergy flares like any other illness or period of physical stress. This requires a proactive approach to monitoring and management. Individuals using insulin may need to check their blood sugar more frequently, perhaps every two to four hours, especially during the height of a reaction or after starting a new allergy medication.
Maintaining hydration is also an immediate step, as dehydration can concentrate blood glucose levels and worsen hyperglycemia. Drinking plenty of sugar-free fluids helps to dilute the sugar in the bloodstream and supports overall metabolic function. Consult with a healthcare provider before making any changes to insulin doses or other diabetes medications.
Dietary choices can help mitigate the inflammatory response that drives the glucose spike. Focusing on specific nutrients can help stabilize blood sugar and prevent sharp post-meal spikes that compound the stress-hormone effect. Having a “sick day” plan prepared with a healthcare team is the best way to navigate allergy season.
Dietary Strategies
- Incorporate foods rich in anti-inflammatory omega-3 fatty acids, such as salmon and walnuts.
- Focus on fiber-rich, low-glycemic carbohydrates.