Those who are sensitive to salicylates find that an excessive amount first stimulates, then depresses the central nervous system. This can lead to a variety of symptoms, including some that might seem incompatible. For example, both hyperactivity and lethargy are associated with salicylate sensitivity.

Symptoms of the condition may include:

• Breathing difficulties
• Wheezing
• Headaches
• Ear infections
• Changes in skin color
• Nasal congestion
• Itching, skin rash or hives
• Swelling of the hands, feet, eyes, lips and face (angioedema)
• Stomach pain
• Hyperactivity
• Lethargy
• Inability to concentrate
• Mouth ulcers, or red rash around the mouth
• Nasal polyps
• Coughing
• Rhinitis
• Sinusitis
• Cognitive and perceptual disorders

In rare cases, sensitivity to salicylate can cause symptoms of anaphylactic shock.