Definition & Overview
Allergic cough is a term used to distinguish cough caused by allergies from cough caused by the common cold. Cough is usually accompanied by a runny nose and nasal congestion, and these symptoms occur simultaneously when a person is suffering from a common cold or allergic reaction. It is sometimes difficult to diagnose and treat a cough because patients are uncertain as to what exactly causes it. As a result, they may take incorrect medications and fail to seek proper medical attention.
Cause of Condition
Allergic cough is primarily caused by an overactive immune system responding excessively to certain substances that the body becomes exposed to. This occurs when the body mistakes harmless substances for harmful ones, and thus initiates a defense system to ward them off. This causes the release of the chemical called histamine, which the body releases when a patient is suffering from a cold. Histamine is responsible for runny noses, coughing, sneezing, and swelling of the nasal passages, so the patient starts experiencing cold-like symptoms even in the absence of the common cold. This is when allergic cough comes in.
There is no one cause behind all allergic reactions, but some people seem more prone to them than others. It usually runs in families, so people with a family history of allergies have a greater chance of developing allergic cough. Studies show that children with one allergic parent have a 33% chance of developing allergies; this number increases to 70% if both parents are allergic.
Allergic cough is also heavily influenced by external factors. It may take an extreme pollen season or moving into a new moldy environment to cause flare-ups to become even worse than normal.
The body also reacts to different allergens; it may be able to flag down some allergens and defend itself, but it may also fall prey to other allergens. The body usually reacts to the allergens by activating mast cells; it is at this point that the symptoms such as allergic cough begin. Once the mast cells burst, the body will be overflowing with histamine. The exposure to the allergen will affect how long the symptoms will be present, and the amount of exposure will also affect the types and severity of symptoms. This is why some people are able to tolerate consuming something or getting exposed to something they are allergic from, but the body reacts when the exposure is continuous, extended, or in excess of what it can handle. This means that there is a specific threshold for triggering allergic cough.
There are key differences in the symptoms of a cough associated with the common cold and allergic cough.
A cough caused by an allergy tends to:
- Lasts for days to months, as long as the allergens are present
- May occur any time of the year, unlike common cold, which occur most often in colder seasons
- Cause sudden symptoms that start as soon as the patient becomes exposed to the allergen
While allergic cough can also be accompanied by a runny nose, itchy and watery eyes, and sore throat, it is never accompanied by fever and body aches. If you have a cough and you are running a fever, it is likely that the cough is caused by the common cold. The common cold also very rarely lasts longer than 14 days, so if a cough does not seem to go away after two weeks and does not seem to be responding to cold treatments and remedies, then it is time to look into the possibility of having allergies.
Allergic cough can also be accompanied by sinus and middle ear infections. These are not considered as symptoms, but as indirect effects of the allergic reaction. Due to the swelling in the nasal passageways, the sinuses become highly sensitive, thus raising the risk of sinus infection, also known as sinusitis. The symptoms of sinus infections include pain around the sinuses (which affects the forehead, upper part and either sides of the nose, upper jaw and upper teeth, cheekbones, and between the eyes), sinus discharge, headache, sore throat, and severe congestion.
However, allergic cough, as well as other symptoms of allergies, can also be outgrown. Most people find that when they enter middle age, their symptoms become less common even when they become exposed to allergens. This is mainly due to the weakening of the immune system and its inability to react as strongly as it used to. However, this does not mean that the allergy itself is gone. Allergies to certain types of food, bee stings, and latex are the ones that are hardest to outgrow.
Who to See & Types of Treatments Available
Since allergic cough is caused by totally different factors, it requires a completely different treatment, which typically involves the following:
- Avoiding allergens or irritants your body is sensitive to; the most common allergens are pollen, mould, animal dander, and dust mites.
- Taking antihistamines, which inhibits the release of histamines and thus, relieves the symptoms such as stuffy nose, runny nose, and swollen nasal passages.
- Taking decongestants, which relieves stuffy and runny nose.
- Taking nasal steroids, which also ease the inflammation and irritation along the nasal passageway, keeping the patient comfortable.
- Undergoing immunotherapy, which means getting allergy shots or small doses of the substance you are allergic to, so that as the dosage increases, the body develops a tolerance to the said substance.
Allergic cough is rarely a serious condition, although its symptoms can be very inconvenient and uncomfortable, especially if the patient does not seek medical assistance. If the allergy is not managed properly, there is a risk of developing asthma. So even if allergy symptoms are very mild, it is still best to see a doctor to seek relief from symptoms as well as long-term protection from complications.
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- Allergy, Immunology and Pulmonary Medicine Journals