Yes, antihistamines have downsides, especially older (first-generation) types that cause significant drowsiness, dry mouth, constipation, and cognitive issues, with long-term use linked to dementia risk; newer (second-generation) antihistamines are generally safer and less sedating but can still cause mild side effects like stomach upset or, rarely, drowsiness at high doses, and prolonged reliance on any antihistamine may signal a need for stronger, root-cause treatments like immunotherapy.
If you're using oral antihistamines very often, you might have wondered if it's OK to keep relying on antihistamines to control symptoms of allergies. The good news is there's no research evidence to suggest regular, long-term use of modern antihistamines is a problem.
H1 first-generation antihistamines: Common adverse effects include sedation, cognitive impairment, and anticholinergic adverse effects such as dry mouth, urinary retention, constipation, and blurred vision. Dizziness, tinnitus, and delirium may occur at high doses.
Helps relieve sensitive itchy skin and temporary travel anxiety, plus soothes insect bites and stings. PetArmor® Antihistamine for Dogs Tablets provide temporary relief from sensitive skin, insect bites and stings, and travel anxiety. They contain the same active ingredient as Benadryl® Allergy Ultratab®*.
Nonprescription anti-itch medicine, called an antihistamine, that doesn't cause drowsiness may help ease itching. Examples include loratadine (Alavert, Claritin, others), famotidine (Pepcid AC), cimetidine (Tagamet HB), nizatidine (Axid AR) and cetirizine (Zyrtec Allergy).
cold, such as cold water or wind. hot, sweaty skin from exercise, emotional stress or eating spicy food. a reaction to a medicine, insect bite or sting. scratching or pressing on your skin, such as wearing itchy or tight clothing.
Fexofenadine (Allegra)
It's one of the least sedating second-generation antihistamines, making it a safe option for long-term use if you take it as your doctor prescribes.
Following are some effective naturally occurring substances that can help relieve allergy signs along with their mechanism of action and how they can be better antihistamines alternatives.
Antihistamine tablets usually start to work within 30 minutes and are likely to be most effective within 1 to 2 hours. For allergies such as hay fever, antihistamines are more effective when taken regularly as a prevention, before symptoms occur, rather than only when you have symptoms.
Antihistamines are usually safe for dogs but can make some dogs drowsy and others hyperactive. OTC antihistamines may contain other ingredients, such as decongestants, that are not safe for dogs. Read the label carefully to ensure that the product only contains antihistamine.
In addition, some antihistamines can make certain health conditions worse. If you have any of the following conditions, you should talk to your healthcare provider first before taking antihistamines: Diabetes. Enlarged prostate or problems passing pee (urinary retention).
Antihistamines, which are commonly used to treat symptoms such as a runny nose or sneezing, are generally safe for patients with abnormal heart conditions. However, the FDA has warned that antihistamines taken in conjunction with some high blood pressure medications may cause a spike in blood pressure.
Certain antihistamines, blood pressure medications, laxatives, diuretics and chemotherapies can cause dehydration, as they cause you to urinate more.
Some long-term side effects that patients have seen include drowsiness, dry eyes, mouth and sinuses, and stomach upset. These continue even after the patient stops taking the medication.
Anxiety caused by antihistamines should go away once you stop taking the medication. If you notice you feel more nervous in the hours following a dose of these allergy medications, speak with your provider about alternatives.
Try not to drink alcohol while taking an antihistamine, particularly if it's a type that makes you drowsy, as it can increase the chances of it making you feel sleepy. Food and other drinks do not affect most antihistamines, but check the leaflet that comes with your medicine to make sure.
For many people with allergies, symptoms are the worst around 4 a.m. to 6 a.m. Taking an antihistamine at bedtime may help you or your child feel better in the morning during allergy season.
Although the degree of involvement may vary from person to person, antihistamines are still widely used as treatment for itching and are often effective, suggesting that histamine is involved to a greater or lesser extent in itchy diseases.
This article describes the eight best natural antihistamines and looks at the science behind them.
As people age, changes in immune responses and immune systems can contribute to the persistence or worsening of existing allergies. Allergy symptoms can intensify over time due to a combination of factors, including the natural aging process, which affects how the body reacts to allergens.
Ginger: A Natural Antihistamine
It helps block histamine release while supporting the immune system. To harness its benefits, prepare ginger tea by steeping fresh slices in hot water for 3–5 minutes. This simple drink can soothe allergy symptoms like congestion and throat irritation.
What is the new FDA warning for Zyrtec and Xyzal? The FDA is requiring a new warning on the labeling for Zyrtec and Xyzal about the risk of severe itching after stopping these medications. For some people, the itching may be serious enough to require medical care.
These are some examples of prescription allergy medicines:
Antihistamines are safe for high blood pressure patients because they don't constrict blood vessels or counteract blood pressure medication. Examples of popular antihistamines include: Loratadine (Claritin) Cetirizine (Zyrtec)