July 2, 2020
Second generation antihistamines have become the mainstay in treating allergies not only due to their fast action but for their non-sedative effect critical in the labor productivity of working people.
Developed in the 1980s to counter the effect of antihistamines that cause sleepiness, second generation antihistamines have become a major advancement in allergy treatment.
This, even with the advantage that it is also a treatment for children, according to Dr. Natividad A. Almazan, in an inaugural webinar “Live with Clarity.” Almazan is head of the Research and Development Office at the Manila Central University College of Medicine & Hospital and a fellow of the Philippine Society of Otolaryngology.
The webinar aims to address the high prevalence of allergies, particularly allergic rhinitis, which affects 1 in 5 Filipinos and around 400 million worldwide, according to the World Health Organization (WHO).
The advantage of anti-allergies not causing one to fall asleep is of primary significance as first generation antihistamines cause much impairment in one’s ability to perform daily tasks.
“The residual effects of poor sleep, including impairment of attention, vigilance, working memory, and sensory motor performance, are still present in the next morning. This is especially problematical with drugs with a long half-life,” according to Martin Church and Diana Church in the “Pharmacology of Anthistamines.”
“The detrimental central nervous system (CNS) effects of first-generation H1-antihistamines on learning and examination performance in children and on impairment of the ability of adults to work, drive and fly aircraft have been reviewed in detail.”
Second generation antihistamines are now also a treatment for children. They have to be more strictly monitored, though, than adults, as expected.
“Both may take the same meds, but the dosage is different. And children should be monitored more,” said Almazan. She said children are 47% likely to have allergic rhinitis when both parents suffer from the allergy.
Allergic rhinitis is common, affecting all age groups, between 10-30% of adults and up to 40% in children & adolescents. This prevalence is higher than skin allergies and asthma.
Patients may experience mild to moderately severe symptoms such as runny nose, nasal obstruction, sneezing, and itchiness that makes it very bothersome.
However, allergic rhinitis can be aggravated by co-morbidities such as asthma, atopic dermatitis, conjunctivitis, sinusitis, polyposis, upper respiratory tract infection, and otitis media, which may render a person unable to conduct daily life normally. As a consequence, this may lead to poor quality of life, sleep disorders, and learning and attention impairment.
The “Live With Clarity” webinar series also provides awareness on common allergens that trigger allergic rhinitis and how to reduce the risk of exposure from them. Pollens are among the ubiquitous allergens with their presence in grasses and flowers, while dust mites are another common type found at home.
Environmental pollution caused by vehicles running on fossil fuels emit carbon dioxide, nitrous oxide, and sulfur dioxide that increase the level of toxins in the air.
Pet animals like dogs or cats may be a trigger for some. Types of seafood, spicy food, cosmetics, and topical products could also cause allergy. Family history also contributes to chances of people getting allergic rhinitis.
How can you tell if you have allergic rhinitis or something else?
According to Dr. Almazan, only specialists can properly diagnose whether a patient is suffering from allergic rhinitis or not. This is typically done by conducting a standard skin prick test done on the patient’s arm. Sterile needles are used to introduce suspected allergens and then the doctor evaluates the skin reaction after 15-30 minutes.
Dr. Almazan stressed that the first step to the treatment of allergic rhinitis is avoidance of triggers.
Also, as a habit, people prone to allergic rhinitis should observe general sanitation—ensuring regular house cleaning and changing of beddings and draperies to prevent dust mites from accumulating. Often, the cause of asthma is the same as that of allergic rhinitis.
For a long time, patients who take oral antihistamines to manage allergic rhinitis feel drowsy or groggy after a short period due to the sedative effects of this medication, which is a common side effect from first or older generation antihistamines.
In most cases, whether intermittent or persistent allergic rhinitis, the main stay treatment is second-generation oral antihistamines. These are considered as non-sedating medication that can be taken in the morning and will not cause drowsiness for an average person who starts the day heading to work.
“Based on a survey on preference for treatment of allergic rhinitis, people prefer the medication targets the symptoms that accompany the condition, has fast action relief, minimal adverse effects, non-habit forming, and long lasting,” says Dr. Almazan. Claritin is a second-generation antihistamine that meets the criteria on what medication is preferred by patients.
Depending on the severity of the allergy, the doctor may prescribe other medications like intranasal corticosteroids (INCS), leukotriene receptor antagonist, decongestants, and immunotherapy.
Dr. Almazan stressed though that all this information should not replace consultation with doctors.
“These medications and treatment approaches have to be monitored, so you have to consult with your doctor and avoid self-diagnosis.”
The “Live With Clarity” series will continue with sessions to focus on allergies in the elderly on July 3 and children & adolescents on July 13. Those interested can check out their schedules at Claritin Philippines’ Facebook page at https://www.facebook.com/claritinphilippines/. (Melody Mendoza Aguiba)