{"id":19878,"date":"2021-03-10T09:30:46","date_gmt":"2021-03-10T14:30:46","guid":{"rendered":"https:\/\/www.singlecare.com\/blog\/?p=19878"},"modified":"2026-04-17T13:09:07","modified_gmt":"2026-04-17T17:09:07","slug":"taking-antihistamines-daily","status":"publish","type":"post","link":"https:\/\/www.singlecare.com\/blog\/taking-antihistamines-daily\/","title":{"rendered":"Is it safe to take an antihistamine every day?"},"content":{"rendered":"

If springtime flowers bring sniffling, sneezing, and itching, you\u2019re not alone. Allergies are one of the most common chronic conditions worldwide, affecting more than 50 million Americans, according to the <\/span>American College of Allergy, Asthma, and Immunology<\/span><\/a>. If you\u2019ve ever faced those pesky symptoms, chances are you\u2019ve taken an antihistamine for relief.\u00a0<\/span><\/p>\n

RELATED: <\/b>Allergy statistics<\/b><\/a><\/p>\n

What are antihistamines?<\/h2>\n

Antihistamines<\/span><\/a> are a class of drugs that generally work by blocking the effects of histamine, a chemical made by your immune system in response to common allergens like mold, dust, pollen, ragweed, <\/span>pet dander<\/span><\/a>, insect bites\/stings, latex, or certain food. The release of too much histamine can spur bothersome symptoms like coughing, sneezing, runny nose, congestion, and itchy eyes, throat, or skin. Severe allergic reactions can lead to swelling and shortness of breath.\u00a0<\/span><\/p>\n

Types of antihistamines<\/span><\/h3>\n

Antihistamines are classified into two groups:\u00a0<\/span><\/p>\n

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  1. First-generation antihistamines <\/b>are effective at blocking the effects of histamine, but they readily cross the blood-brain barrier. As a result, they are often associated with certain side effects like drowsiness, sedation, and fatigue. Popular brand names of first-generation antihistamines include <\/span>Benadryl<\/span><\/a>, <\/span>Unisom<\/span><\/a>, and <\/span>Vistaril<\/span><\/a>.\u00a0<\/span><\/li>\n
  2. Second-generation antihistamines <\/b>are newer antihistamines that don\u2019t cross the blood-brain barrier as easily as first-generation antihistamines. Therefore, they carry a lower risk of drowsiness. Because they are less sedating and don\u2019t interact with as many drugs as their first-generation counterparts,<\/span> research<\/span><\/a> says second-generation antihistamines are safer. <\/span>Allegra<\/span><\/a>, <\/span>Claritin<\/span><\/a>, and <\/span>Zyrtec<\/span><\/a> are some common brand names in this group.<\/span><\/li>\n<\/ol>\n

    Seasonal allergies are typically limited to the spring, summer, and early fall, but perennial allergies can occur year-round. If it\u2019s not possible to eliminate exposure to your allergy trigger, you may keep daily symptoms under control with an over-the-counter (OTC) or prescription antihistamine.<\/span><\/p>\n

    Oral antihistamines generally start to <\/span>work <\/span>within 30 minutes, reaching maximum effect in about 2 hours. But when it comes to allergy medications for seasonal allergies, it\u2019s best to start taking them <\/span>preventively<\/span><\/a> 2-4 weeks before you expect your allergic symptoms to start. If you\u2019re using eye drops for itchy, watery eyes, they work immediately, but steroid nasal sprays can take a few days to kick in.\u00a0<\/span><\/p>\n

    RELATED:<\/b> Allergy Meds 101: Your seasonal allergy med questions answered<\/b><\/a><\/p>\n

    Is it safe to take an antihistamine daily?<\/h2>\n

    Experts say, it\u2019s usually okay. \u201cTaken in the recommended doses, antihistamines can be taken daily, but patients should make sure they do not interact with their other medications,\u201d <\/span>says <\/span>Sandra Lin, MD<\/span><\/a>, professor and chair of Otolaryngology-Head & Neck Surgery at the University of Wisconsin<\/span>.<\/span>\u00a0<\/span><\/p>\n

    In other words, you\u2019ll need to make sure that you choose the right antihistamine for everyday use. First-generation antihistamines come with an increased risk of certain side effects and drug interactions, so they are not generally advised for long-term usage.<\/span><\/p>\n

    \u201cWith first-generation antihistamines, some people note decreasing effectiveness if used daily for several days,\u201d says Dr. Lin. Because they cause drowsiness, they are not safe to mix with alcohol\u2014something to consider if you plan to have a drink during allergy season.<\/span><\/p>\n

    RELATED:<\/b> Is it safe to drink alcohol while taking allergy medicine?<\/b><\/a><\/p>\n

    The risk of interaction increases with combination products. Some allergy medications contain an antihistamine and a decongestant (e.g., Claritin D). \u201cThe decongestant component can cause elevated blood pressure and elevated heart rate,\u201d says<\/span> Stephen Tilles, MD<\/span><\/a>, clinical professor of medicine at the University of Washington. However, Dr. Lin says antihistamines alone are \u201cnot bad for the heart in otherwise healthy people.\u201d<\/span><\/p>\n

    \u201cThe later generation non-sedating antihistamines, such as loratadine, fexofenadine, and cetirizine are safe to take daily,\u201d says John Faraci, MD<\/a>, an allergist and immunologist in\u00a0 Loma Linda, California<\/span>. \u201cIn some people, cetirizine may cause people to feel sleepy or drowsy, but it\u2019s unlikely.\u201d Second-generation antihistamines can remain effective when you take them every day.<\/span><\/p>\n

    It\u2019s important to note that long-term use of first-generation antihistamines, like Benadryl, may increase the risk of dementia and cognitive decline, <\/span>research<\/span><\/a> suggests. And there\u2019s always a risk of taking too much of an antihistamine, especially with long-term use. An antihistamine overdose can cause various symptoms of toxicity, such as severe drowsiness, blurred vision, hallucinations, and seizures.<\/span><\/p>\n

    Use this table as a quick reference guide for which medications are safe, but always consult with your pharmacist or healthcare provider before adding a medication to your daily regimen.<\/span><\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
    \n

    Safety and dosage guidelines for daily use of antihistamines<\/h3>\n<\/th>\n<\/tr>\n<\/thead>\n

    Drug name<\/b><\/td>\nGeneration<\/b><\/td>\nRecommended dosage for otherwise healthy adults<\/b><\/td>\nSafe to take daily?<\/b><\/td>\nGet coupon<\/b><\/td>\n<\/tr>\n
    Aller-Chlor (chlorpheniramine)<\/span><\/td>\nFirst<\/span><\/td>\n4 mg every 4 to 6 hours (maximum of 24 mg per day)<\/span><\/td>\nNo<\/span><\/td>\nChlorpheniramine coupons<\/span><\/a><\/td>\n<\/tr>\n
    Benadryl (diphenhydramine)<\/span><\/td>\nFirst<\/span><\/td>\n25 to 50 mg every 4 to 6 hours (maximum of 300 mg per day)<\/span><\/td>\nNo<\/span><\/td>\nBenadryl coupons<\/span><\/a><\/td>\n<\/tr>\n
    Bromax (brompheniramine)<\/span><\/td>\nFirst<\/span><\/td>\n6 to 12 mg every 12 hours (maximum of 24 mg per day)<\/span><\/td>\nNo<\/span><\/td>\nBrompheniramine coupons<\/span><\/a><\/td>\n<\/tr>\n
    Periactin (<\/span>cyproheptadine)<\/span><\/td>\nFirst<\/span><\/td>\n4 to 20 mg per day in divided doses (maximum of 0.5 mg\/kg per day or 32 mg per day, whichever is less)<\/span><\/td>\nNo<\/span><\/td>\nCyproheptadine coupons<\/span><\/a><\/td>\n<\/tr>\n
    Ryclora (<\/span>dexchlorpheniramine)<\/span><\/td>\nFirst<\/span><\/td>\n2 mg every 4 to 6 hours (maximum of 12 mg per day)<\/span><\/td>\nNo<\/span><\/td>\nRyclora coupons<\/span><\/a><\/td>\n<\/tr>\n
    Tavist (<\/span>clemastine)<\/span><\/td>\nFirst<\/span><\/td>\n1.34 mg every 12 hours (maximum of 2.68 mg per day)<\/span><\/td>\nNo<\/span><\/td>\nClemastine coupons<\/span><\/a><\/td>\n<\/tr>\n
    Aldex AN (doxylamine)<\/span><\/td>\nFirst<\/span><\/td>\n10 mg every 4 to 6 hours (maximum of 60 mg per day)<\/span><\/td>\nNo<\/span><\/td>\nDoxylamine coupons<\/span><\/a><\/td>\n<\/tr>\n
    Vistaril (<\/span>hydroxyzine)<\/span><\/td>\nFirst<\/span><\/td>\n25 mg 3 to 4 times per day (maximum of 100 mg per day)<\/span><\/td>\nYes<\/span><\/td>\nHydroxyzine coupons<\/span><\/a><\/td>\n<\/tr>\n
    Allegra (fexofenadine)<\/span><\/td>\nSecond<\/span><\/td>\n60 mg twice per day or 180 mg once per day (maximum of 120 mg if taken twice per day or 180 mg if taken once per day)<\/span><\/td>\nYes<\/span><\/td>\nFexofenadine coupons<\/span><\/a><\/td>\n<\/tr>\n
    Clarinex (desloratadine)<\/span><\/td>\nSecond<\/span><\/td>\n5 mg once per day (maximum of 5 mg per day)<\/span><\/td>\nYes<\/span><\/td>\nDesloratadine coupons<\/span><\/a><\/td>\n<\/tr>\n
    Claritin (loratadine)<\/span><\/td>\nSecond<\/span><\/td>\n10 mg once per day (maximum of 10 mg per day)<\/span><\/td>\nYes<\/span><\/td>\nClaritin coupons<\/span><\/a><\/td>\n<\/tr>\n
    Zyrtec (cetirizine)<\/span><\/td>\nSecond<\/span><\/td>\n5 to 10 mg daily (maximum of 10 mg per day)<\/span><\/td>\nYes<\/span><\/td>\nCetirizine coupons<\/span><\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

    Are there side effects from taking antihistamines daily?<\/h2>\n

    First-generation antihistamines can cause side effects such as:<\/span><\/p>\n