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Antihistamines can cause serious effects on your Health !!

Antihistamines are a group of medications that are usually used to treat various conditions including allergies and nausea and even vomiting. These are usually available as per the doctor’s prescription or can be bought at pharmacies. However, researchers are coming to the conclusion that these medications may have some serious effects on a person’s health. 

Read more to find out why how these medications can cause problems in two groups of people - children with cough problems and even pregnant women.  

What are Antihistamines?

An Antihistamine is a drug which serves to decrease or completely eliminate effects mediated by histamine, an endogenous chemical mediator which is released during allergic reactions or through actions caused at the histamine receptor. 

Children shouldn’t always take Antihistamines for a chronic cough !!

So what are histamines?

Histamines are a compound found in nearly all tissues of the body plays a bigger role in allergic reactions. It is normally released in allergic conditions, including asthma and further gives rise to the symptoms. Antihistamine drugs inhibit these histamines. 

The Study !! 

Researchers have found out that antihistamines can alleviate a cough only upto some extent and the possible side effects may outweigh their benefits.

  • A child is usually considered to have a chronic cough after a period of 4 weeks. 
  • A specific cough may be linked with symptoms suggestive of an underlying condition.
  • A non-specific cough may be a non-productive cough without the sputum which occurs in the absence of identifiable respiratory disease.

Children diagnosed with a non-specific cough are treated with a variety of therapies including antihistamines. 

Researchers examined five studies about 1000 children, ranging from six months to 17 years old. Most of these children were found to be allergic to things like grass, pollen or dust mites or maybe even have a family history of allergies. 

The effectiveness of Antihistamines based on Study findings!!

Two larger studies described significant improvement both in children who took antihistamines and those who took placebos with no significant difference between the two groups. 

Another smaller study which involved 20 school-age children found that cetirizine( Zyrtec) clinically improved cough problems due to pollen allergy. In the same study, the antihistamine was much more effective than placebos in reducing chronic cough in children with allergies. 

A third study investigated the use of ketotifen (Zaditen) to decrease the frequency of asthma attacks in 113 infants ranging from six months to 36 months old. After a 4-week-mo-medication period, infants received either a placebo or ketotifen for 16 weeks. Researchers concluded that they were not able to display a therapeutic advantage of ketotifen over placebo.

The effectiveness of the drugs should be analyzed against their reported side effects, especially in young children including -

  • Sedation
  • Paradoxical excitability 
  • Dizziness
  • Respiratory depression
  •  Hallucinations
  • Arrhythmia and even Death.

In most of these studies, most of the events reported were minor with irritability and gastrointestinal issues being the most common events. In one case 4 children were withdrawn from the study. A dozen other children even felt drowsy after taking the medicine.

The Effectiveness of Old and New Antihistamines !!

According to the researchers, all Antihistamines aren’t equal and can have different effects depending on the nature of the ingredients involved.

  • Older antihistamines (such as Benadryl) work well, usually when the cause of the upper airway cough is not due to allergies and they can also work if the cause of a cough is only caused by allergies.
  • Newer antihistamines such as cetirizine(Zyrtec) or loratadine (Claritin) don’t really possess much anticholinergic activity and will only work if the cause of the upper airway cough is due to allergies.

However, researchers also found out that newer antihistamines like Zyrtec were shown to help children who suffered from allergic rhinitis. The studies also further proved that using Specific antihistamines when children had coughing problems were linked with seasonal allergies that involved the nose.  

What do the researchers have to say?

Studies have shown that parents continue to seek treatment for their children, spending billions of dollars worldwide only on cough and allergy medications each year. 

  • First of all, it is important to find out the reasons behind the cause of a cough 
  • Secondly, physicians should talk to the parents about their fears and concerns.
  • Thirdly parents who smoke inside the premises of the house should stop as it is directly affecting the children.
  • The doctors should use a more, wait-see-and-review kind of approach with their patients suffering from a non-specific cough.

A group of previously conducted researches was reviewed by some researchers, led by Dr. Anne Chang, a consultant in pediatric respiratory medicine at the Royal Children’s Hospital in Brisbane and the Menzies School of Health Research in Queensland to come up with these findings.

 Risk of Birth Defects among women who take antihistamines during Pregnancy !!

Antihistamines were often used by women during their pregnancy. These antihistamines sometimes require a prescription while most of them are available over-the-counter or OTC medications.

A new study from Boston University has found out that women could be at risks if they frequently used antihistamines medications during their pregnancy periods.

The findings were based on interviews with more than 20,00 new mothers. Researcher considered antihistamines that had been suggested in earlier studies to increase the risks of certain defects and also considered the other possible risks that might still not have been identified in the past.

According to one researcher, the newly conducted studies and findings have shown results that question the relative safety of many of these medications in relation to a number of common birth defects.

Just like most other medications, women who are pregnant or may become pregnant should go and consult with their health care provider before taking any sort of medications regardless of whether the medication is prescribed or over-the-counter medication.

The research was carried out by Dr. Allen Mitchell from Boston University’s Slone Epidemiology Center.