Apart from allergies there can be some severe complications and they are:

Acute sinusitis – sinuses are the air filled hollow cavities around the nose and nasal passages, when inflamed, fluid may accumulate and interfere with the normal drainage of mucus in the sinuses and this is called as an acute sinusitis.

The symptoms are difficulty in breathing, pain, headache, fever, cough and swelling of the eyes and face. Although bacteria and allergies may be the reason, common cold virus is the most frequent reason for this condition.

The therapies can be from antibiotics to corticosteroids for acute inflammation.

Most of the symptoms are vanished shortly, if the symptoms last less than four weeks, it is considered acute.

Chronic sinusitis – In most of the cases sinusitis are acute, they disappear in less than four weeks. If this condition lasts more than four weeks or recurs, then it is a developed case of chronic sinusitis.

Dermatographia – it is a condition where the skin is over sensitive to light, scratching resulting in red lines there, it is not serious but may be uncomfortable. The symptoms are redness, itching and swelling. If they last long antihistamines and self-care measures can help to manage this skin problems.

Hives and angioedema – it is also known as urticaria in which batches of raised, red or white itchy wheals of various sizes appear and disappear on the skin.

Asthma – the relationship between allergies and asthma are very much interlinked.

Nasal polyps – small nasal polyps may usually cause few problems, but larger one can affect your breathing and your sense of smell is diminished. It is more common in persons above 40 years and also in adults and in children with asthma, chronic sinus infections, hay fever and cystic fibrosis.

Medications are the common treatment for small nasal polyps, but surgery is the choice to remove larger polyps.

Anaphylaxis – it is a dangerous and life-threatening allergic reaction and the common triggers are foods, insect venoms, latex and certain drugs. The allergic symptoms are watery eyes and a runny nose. Anaphylaxis floods many chemicals in the body which makes your blood pressure drop suddenly, difficulty in breathing, unconsciousness and death. This effect may be in seconds or in few minutes. It can be venom from bee sting or an ingested groundnut or a drug, like penicillin.

Fortunately, anaphylaxis is the least common allergic reaction and at the same time the doctors and the emergency centres could help you very quickly.