T78: Adverse effects, not elsewhere classified
T78.4: Allergy, unspecified
With an allergy, the immune system overreacts to certain substances. Such substances may be harmless substances in the environment, drugs or certain chemicals, for example.
An allergy may be accompanied by a range of symptoms. For example, you may experience sneezing, swellings or changes to your skin. The eyes and skin may feel itchy. When allergic reactions are very severe, you may suffer from breathlessness or circulatory problems.
Patient Disclaimer
The information provided on this page is for general educational purposes only. It is not intended for self-diagnosis and does not replace professional medical advice. Always consult your doctor or a qualified healthcare provider with any questions or concerns about your health.
If you see an ICD diagnosis code (e.g., on a medical report), be aware that doctors may also include additional indicators to express diagnostic certainty. Only a healthcare professional can interpret these codes accurately in the context of your individual case.
For a complete understanding of your condition and what the diagnosis means for you, please speak directly with your doctor.