Best antihistamine for seniors (and the interactions to watch for)

In this article:

• Antihistamine use in older adults
• Second-generation antihistamines
• First-generation antihistamines
• Blood pressure medication
• Glaucoma
• Enlarged prostate
• Safety checklist
• How to save
• Bottom line
• FAQs

In this article

• Antihistamine use in older adults
• Second-generation antihistamines
• First-generation antihistamines
• Blood pressure medication
• Glaucoma
• Enlarged prostate
• Safety checklist
• How to save
• Bottom line
• FAQs

It can be frustrating to deal with allergies no matter your age, but in older adults, choosing an antihistamine can be a little more complicated. In those over 65, especially those with glaucoma, high blood pressure, or an enlarged prostate, certain medications carry additional risks.

The good news is that newer antihistamine options provide allergy relief without some of the side effects or risks that are problematic for older adults. If you’re searching for a solution for issues like hay fever, allergic rhinitis, or annoying sneezing and itchy eyes, this article will help you understand the difference between antihistamine generations and give tips to help you choose a safe option.

Why antihistamine choice matters more after 65

Antihistamine choice matters more for older adults because, as Erika Gray, Pharm.D., chief medical officer at ToolBox Genomics.com says, “That’s when life choices like to catch up to us!”

“Over the age of 65, individuals start to undergo different physiological changes especially with their liver and kidneys. For example, consuming alcohol in the past means our liver isn’t as capable as it once was,” she explains. “As we age, our liver and kidneys have a decreased ability to break down and excrete the medications, meaning the drug often stays around longer.”

Additionally, there are two types of antihistamines (classified as first- and second-generation drugs), and first-generation antihistamines are generally not preferred in older people.

The first generation came along during the 1940s and includes medications like Benadryl (diphenhydramine) and hydroxyzine. They work by blocking a chemical messenger known as acetylcholine as well as blocking histamine. This is known as an anticholinergic effect.

Acetylcholine plays an important role in regulating a lot of your body’s normal operations, like memory, attention, digestion, saliva production, and even bladder function. When first-generation antihistamines block acetylcholine, they can cause unwanted side effects like constipation, dry mouth, trouble urinating, blurred vision, confusion, falls, delirium, and drowsiness.

These side effects can be troubling for anyone, but they become more concerning with age. Many older adults take several medications or have multiple health conditions, and your body starts processing medications differently as it ages. It may take longer for drugs to leave your system, or you may have more comorbidities.

This can lead to what is known as an anticholinergic burden, which is the cumulative effect of taking several medications that block acetylcholine.

The American Geriatrics Society’s Beers Criteria actually identifies a number of first-generation antihistamines as medications that older adults should avoid due to their strong anticholinergic properties. These include the following generic medications:

• Brompheniramine
• Chlorpheniramine
• Cyproheptadine
• Dimenhydrinate
• Diphenhydramine
• Doxylamine
• Hydroxyzine
• Meclizine
• Promethazine
• Triprolidine

Generally, second-generation antihistamines are preferable for older adults.

Best antihistamines for seniors: Second-generation options

If you’re looking for a starting point, second-generation antihistamines offer a better option for older adults. Around the mid-1980s, the FDA approved the first second-generation antihistamine (terfenadine), paving the way for drugs like loratadine, fexofenadine, and cetirizine.

These medications offer allergy relief without as many central nervous system effects as their first-generation counterparts. The older first-generation drugs are fat-soluble and easily cross the blood-brain barrier, whereas second-generation options are lipophobic (water-soluble) and are largely blocked from doing so.

The most common second-generation antihistamines include:

• Zyrtec (cetirizine): Generally less sedating than first-generation drugs and highly effective at treating allergies, though some people may still experience drowsiness.  The drowsiness may decrease after taking the medication for a few weeks.
• Claritin (loratadine): Has a very low risk of drowsiness and may be a good option for those looking to avoid daytime sedation while dealing with mild, everyday allergies
• Allegra (fexofenadine): Has the lowest risk of drowsiness and is ideal for those needing to be alert

“Loratadine is considered the best and most well-studied ‘first line’ option because it doesn’t affect the CNS and sedation is minimal,” Dr. Gray explains.

While second-generation antihistamines are preferable to first-generation medications in older adults, there are still some key considerations. For example, if you have liver or kidney issues, you may need to adjust your dosage to avoid severe complications. Talk with your provider before starting an antihistamine and alert them to any health conditions and medications you currently take.

Antihistamine	Generation	Considerations for older adults
Zyrtec (cetirizine)	Second	Generally less sedating but may still cause some drowsiness. Consult a provider about dosing if you have kidney issues.
Claritin (loratadine)	Second	Very low risk of drowsiness but may require dose adjustments in those with kidney or liver issues.
Allegra (fexofenadine)	Second	Very low risk of drowsiness but may require a lower dose in those with kidney issues.
Benadryl (diphenhydramine)	First	High risk of drowsiness, confusion, dry mouth, urinary retention, and falls.
Hydroxyzine	First	High risk of intense sedation, cognitive impairment, confusion, and falls.

Antihistamines to use with caution: First-generation options

Most people have heard of Benadryl (diphenhydramine); it may be the best-known first-generation antihistamine. It is highly effective at treating allergy symptoms, but it can cause significant anticholinergic side effects, particularly drowsiness. Benadryl is still considered a first-line medication to take if you are having a severe allergic reaction.

Hydroxyzine is another first-generation antihistamine that has sedating and other anticholinergic effects. Some providers prescribe it for issues like anxiety or itching, though it isn’t typically the first choice for those who have routine allergies.

With either of these drugs, the anticholinergic effects are especially risky for older adults. After taking them, you may experience unsteadiness, dizziness, confusion, falls, difficulty urinating due to urinary retention, or constipation. This is why the most recent AGS Beers Criteria recommend that older adults avoid these drugs.

“Older adults should generally avoid first-generation antihistamines such as diphenhydramine, hydroxyzine, chlorpheniramine, and promethazine because these medications cross the blood-brain barrier and are more likely to cause sedation, confusion, and memory or concentration problems,” emphasizes Vernilyn N. Juan, MD, primary care provider at LCMC Health in New Orleans.

Keep in mind, there may be a legitimate use for first-generation antihistamines in older adults; however, only under the guidance of a healthcare provider who can weigh the risks and benefits.

Antihistamines and blood pressure medication

If you are on medication to manage your blood pressure, there are antihistamines that are generally safe to take. The concern is usually that some antihistamines have an added decongestant, like pseudoephedrine or phenylephrine. You may see these added to brand-name drugs that tack a “-D” at the end of their name, like Allegra-D or Claritin-D.

Decongestants are effective, but they work, in part, by constricting your blood vessels. This can raise your blood pressure and is why the American Heart Association recommends that if you have high blood pressure, you should consult with your provider before taking a decongestant.

Fortunately, you can still take single-ingredient antihistamines like Zyrtec if you have high blood pressure or if you’re on hypertension medication.

“In general, second-generation antihistamines such as loratadine, cetirizine, desloratadine, levocetirizine, and fexofenadine are less likely to cause problems when taken with common blood pressure medications,” Dr. Juan says. “However, older adults should still review their medications with their healthcare provider or pharmacist before starting a new over-the-counter medication.”

RELATED: Does Benadryl raise your blood pressure? 

Antihistamines and glaucoma

If you have narrow-angle glaucoma (or angle-closure glaucoma), you should likely avoid first-generation antihistamines. Medicines with anticholinergic properties may cause your pupils to dilate or otherwise narrow the drainage angles in the eye. This can lead to an acute angle-closure glaucoma attack, which is an emergency because your eyes cannot drain fluid.

Second-generation antihistamines have much lower anticholinergic activity and are typically preferred for older adults with glaucoma. However, if you have glaucoma, talk to your ophthalmologist or pharmacist before starting any type of medication.

Antihistamines and an enlarged prostate (BPH)

An enlarged prostate is also known as benign prostatic hyperplasia (BPH). This condition can make it difficult to empty your bladder. Medications with anticholinergic effects can further interfere with your bladder’s function, making urination even more difficult.

This happens because certain drugs, like first-generation antihistamines, can reduce your bladder muscle’s ability to contract. Those contractions are necessary to empty urine from the bladder. Because BPH already leads to a narrowed urethra, the added complication from an anticholinergic medication can lead to urinary retention.

If you have BPH and you already have symptoms like difficulty urinating, a weak stream, or frequent urination, talk with a healthcare professional before taking an antihistamine.

Second-generation antihistamines, like loratadine and cetirizine, have a lower anticholinergic profile and are generally preferred for people with BPH.

How to choose a safer antihistamine: A quick checklist

Before you take an antihistamine for issues like allergic conjunctivitis, runny nose,  pet dander, or hives, here are a few steps to consider:

• Review your full list of medications: Ask a pharmacist or healthcare provider about potential drug interactions.
• Avoid “-D” combination products: The decongestant in these may be problematic for those with high blood pressure.
• Talk to a provider or allergist about your health history: Make sure your provider knows about any medical conditions, especially high blood pressure, glaucoma, or BPH.
• Start with a second-generation antihistamine: These are generally safer options for older adults due to their lower anticholinergic profile.
• Consider your need for alertness: Even some second-generation antihistamines can cause slight drowsiness.
• Don’t combine antihistamines: Unless your provider has instructed you to do so, avoid taking more than one antihistamine at a time. If you are taking over the counter cold medicine, consider buying only single-ingredient medications so you know what is in them.
• Be on the lookout for side effects: If you experience dry mouth, constipation, blurred vision, confusion, or difficulty urinating, contact your healthcare provider.

How to save money on senior-safe antihistamines

You don’t need to pay more for a medication that is appropriate for an older adult. Generic cetirizine, loratadine, desloratadine, and fexofenadine are available over the counter and tend to be less expensive than their brand-name counterparts.

If you’re looking to save money, you can use SingleCare coupons for OTC antihistamines as long as you have a prescription from your healthcare provider. This can lower the cost of even generic medications, including azelastine, which can be either eye drops or a nasal spray.

Bottom line

Safe, effective allergy relief is available for older adults, including those who may be taking blood pressure medications, managing glaucoma, or living with BPH. For many people, consulting with a provider and taking a second-generation antihistamine is an effective solution.

Frequently asked questions

Do antihistamines increase dementia in older adults? 

Research has found that there is a link between anticholinergic antihistamines and dementia in older adults. A study of 3,500 people older than 65 noted that “taking an anticholinergic for three years or more was associated with a 54% higher dementia risk than taking the same dose for three months or less.” This is one of the reasons that experts advise against older adults taking first-generation antihistamines long-term.

Is Xyzal (levocetirizine) safe for seniors? 

Xyzal is a second-generation antihistamine and accordingly has fewer sedative effects compared to first-generation antihistamines. It can, however, still cause drowsiness and may not be ideal for those with impaired kidney function. It’s very closely related to Zyrtec, though drugs like Claritin and Allegra may be the preferred choice for older adults due to sedation and kidney function concerns.

Is it ever okay for a senior to take Benadryl occasionally, like for a one-time allergic reaction? 

Yes. A healthcare provider may recommend that an older adult take Benadryl, generically called diphenhydramine, occasionally, such as when an allergic reaction occurs. However, it can cause significant drowsiness, blurred vision, and confusion, which can be problematic for those at risk of falls. Therefore, acute (or occasional) use is preferable to daily use, and should only happen under the care of a provider.