From the Guidelines
A histamine plasma level of 1.51 ng/mL is generally within the normal reference range, which typically falls between 0.3-1.5 ng/mL, though exact ranges may vary slightly between laboratories. This level is at the upper end of normal and doesn't necessarily indicate a problem. Histamine levels can fluctuate based on several factors including time of day, recent food consumption (especially histamine-rich foods like aged cheese, fermented foods, or alcohol), medication use, or environmental exposures 1. If you're experiencing symptoms like flushing, headaches, or digestive issues despite this borderline level, you might consider keeping a food diary to identify potential triggers. Some medications that can help manage histamine-related symptoms include antihistamines like cetirizine (10mg daily) or fexofenadine (180mg daily) 1. Histamine is a chemical messenger involved in immune responses and inflammation, produced by mast cells and basophils in your body. It plays important roles in allergic reactions, stomach acid production, and even brain function as a neurotransmitter. Minor elevations often don't require treatment unless accompanied by symptoms. It's also important to note that anaphylaxis, a severe allergic reaction, can be associated with increased histamine levels, but diagnosis and management should follow established criteria and guidelines, such as those outlined by the NIAID/FAAN 1. In any case, consultation with a healthcare professional is recommended for proper evaluation and guidance. Key points to consider include:
- Histamine levels can fluctuate and may not always indicate a problem
- Keeping a food diary can help identify potential triggers for symptoms
- Antihistamines may be used to manage histamine-related symptoms
- Anaphylaxis diagnosis and management should follow established guidelines.
From the Research
Histamine Plasma Levels
- The normal range for histamine plasma levels is not explicitly stated in the provided studies, but we can look at the values mentioned in the studies to get an idea of what might be considered normal or elevated.
- In the study 2, resting plasma histamine levels were 0.62 +/- 0.12 ng/ml.
- In the study 3, the upper limit of normal for plasma histamine levels was 617 pg/mL.
Comparison to Your Histamine Level
- Your histamine plasma level is 1.51, which is higher than the resting plasma histamine level mentioned in study 2 (0.62 +/- 0.12 ng/ml) and also higher than the upper limit of normal mentioned in study 3 (617 pg/mL).
- However, it's essential to note that the units used in the studies are different (ng/ml vs pg/mL), so a direct comparison might not be possible without converting the units.
Possible Causes of Elevated Histamine Levels
- Elevated histamine levels can be caused by various factors, including histamine intolerance, food allergies, or mast cell disorders.
- Study 4 found that 24% of patients with suspected histamine intolerance had elevated histamine levels, which might be caused by reduced activity of diamine oxidase (DAO).
- Study 5 found that elevated histamine levels were observed in 42% of patients with acute allergic reactions, and histamine levels correlated better with clinical signs than tryptase levels.
Clinical Significance of Elevated Histamine Levels
- Elevated histamine levels can cause various symptoms, including flushing, headaches, tachycardia, and diastolic hypotension, as mentioned in study 2.
- Study 6 found that corticosteroid therapy caused a marked fall in whole blood histamine concentration and restored plasma levels to normal in patients with severe asthma.
- Study 3 found that patients with mastocytosis tended to show moderate to marked elevations in plasma histamine levels, and plasma histamine determinations alone were not useful to screen patients for mastocytosis.