From the Guidelines
No, you should not take a double dose of over-the-counter oral antihistamines for allergy symptoms, wheezing, and cough due to mold exposure without consulting a healthcare provider first. Standard antihistamines like cetirizine (Zyrtec), loratadine (Claritin), or diphenhydramine (Benadryl) should be taken according to the package instructions, typically once or twice daily depending on the specific medication. Exceeding the recommended dose can increase the risk of side effects such as extreme drowsiness, dry mouth, blurred vision, urinary retention, and in severe cases, heart rhythm disturbances. For mold-related symptoms, particularly wheezing and cough, antihistamines alone may not be sufficient treatment. These symptoms might indicate a more serious respiratory reaction that could require additional medications like inhaled bronchodilators or corticosteroids. If you're experiencing wheezing, which suggests airway constriction, seek medical attention promptly as this could potentially develop into a more serious respiratory condition requiring different treatment approaches, as suggested by guidelines for managing allergic rhinitis 1. However, it's worth noting that in some cases, increasing the dose of second-generation H1 antihistamines above the licensed recommendation may be considered when benefits outweigh risks, as mentioned in guidelines for urticaria management 1. But for over-the-counter use and without specific guidance from a healthcare provider, sticking to the recommended dosage is crucial to minimize potential side effects and ensure safety. Given the potential for more severe respiratory symptoms with mold exposure, consulting a healthcare provider is essential for appropriate diagnosis and treatment, which may involve a combination of medications including antihistamines, inhaled corticosteroids, or bronchodilators, as indicated by the most recent and highest quality studies on pharmacologic treatment of seasonal allergic rhinitis 1.
From the Research
Allergy Symptoms and Treatment
- Allergic rhinitis is an inflammatory disease of the nasal mucosa, caused by an IgE-mediated reaction after exposure to the allergen to which the patient is sensitized 2.
- Symptoms of allergic rhinitis include nasal congestion, rhinorrhea, postnasal drainage, sneezing, and itching of the eyes, nose, and throat 3.
- Treatment for mild intermittent or mild persistent allergic rhinitis may include a second-generation H1 antihistamine or an intranasal antihistamine, while patients with persistent moderate to severe allergic rhinitis should be treated initially with an intranasal corticosteroid either alone or in combination with an intranasal antihistamine 3.
Double Dose of Antihistamines
- A study compared the efficacy and side effects of combined therapy with single-dose oral antihistamine and intranasal corticosteroid to monotherapy with double-dose oral antihistamine in the treatment of seasonal allergic rhinitis, and found that the combined therapy was superior to the monotherapy with double-dose oral antihistamine 4.
- There is no clear evidence to support the use of double-dose antihistamines for allergy symptoms, wheezing, and cough due to mold exposure, and treatment should be individualized according to the concrete characteristics of each patient 2.
Antihistamine Therapy
- Antihistamines, particularly second-generation drugs, have been shown to exert an anti-inflammatory effect, which is greater when the drug is administered continuously than when administered upon demand 2.
- Continuous antihistamine therapy may reduce treatment cost and improve quality of life among patients, but the indication of treatment on a continuous basis or upon demand should be individualized according to the patient's characteristics 2.