What antihistamines should elderly avoid? Your guide to safer allergy relief

According to the American Geriatrics Society (AGS) Beers Criteria, first-generation antihistamines are generally recommended for older adults to avoid. Understanding what antihistamines should elderly avoid is crucial for preventing significant side effects such as confusion, falls, and cognitive impairment. This guide explores why certain antihistamines pose a greater risk and highlights safer alternatives for allergy relief in seniors.

Quick Summary

First-generation antihistamines, known for causing sedation and anticholinergic effects, are generally not recommended for seniors due to increased risks of confusion, falls, and other adverse effects. Newer, second-generation antihistamines are a much safer alternative for managing allergy symptoms in older adults. Always consult a doctor before starting any new medication to ensure safety and effectiveness.

Key Points

• Avoid First-Generation Antihistamines: Older, first-generation antihistamines like Benadryl (diphenhydramine) should be avoided by the elderly due to a higher risk of severe side effects.

• Risk of Cognitive Impairment: First-generation antihistamines can easily cross the blood-brain barrier, leading to confusion, reduced mental alertness, and an increased risk of dementia with long-term use.

• Increased Risk of Falls: Sedation and dizziness caused by older antihistamines significantly increase the risk of falls, a major concern for senior health.

• Strong Anticholinergic Effects: These medications can cause adverse anticholinergic effects like dry mouth, blurred vision, constipation, and urinary retention.

• Choose Second-Generation Alternatives: Safer options for seniors include second-generation antihistamines like Claritin (loratadine), Zyrtec (cetirizine), and Allegra (fexofenadine).

• Consult a Doctor: Before using any new medication, especially in the elderly, it is crucial to consult a healthcare provider to ensure safety and check for interactions with other medications.

• Consider Second-Generation Options: Second-generation options like Zyrtec may be suitable for older adults, particularly considering individual health factors and kidney function.

Why Older Adults are More Sensitive to Certain Medications

As the body ages, metabolic and physiological changes occur that can affect how medications are processed. The liver and kidneys may become less efficient at clearing drugs from the system, meaning medications can remain active in the body longer and potentially cause more side effects. These changes make older adults more susceptible to adverse effects from certain drugs, particularly those that impact the central nervous system, like first-generation antihistamines.

The Antihistamines the Elderly Should Avoid

The primary antihistamines to avoid are the older, first-generation versions, which are known for their sedating and strong anticholinergic properties. Many of these are available over-the-counter and are also found in multi-symptom cold and flu products.

Common first-generation antihistamines to avoid include:

• Diphenhydramine: (Benadryl, Nytol, Sominex, ZzzQuil)
• Chlorpheniramine: (Chlor-Trimeton, often in combination cold products)
• Dimenhydrinate: (Dramamine)
• Doxylamine: (Unisom, Vicks NyQuil)
• Hydroxyzine: (Atarax, Vistaril, available by prescription)
• Promethazine: (Phenergan, available by prescription)

The Dangers of First-Generation Antihistamines for Seniors

First-generation antihistamines are risky for older adults for several key reasons.

Central Nervous System (CNS) Effects: These drugs are "lipophilic," meaning they can easily cross the blood-brain barrier and affect the brain directly. This leads to significant CNS side effects such as:

• Drowsiness and sedation: This can persist long after taking the medication, interfering with daytime activities and driving.
• Confusion and reduced mental alertness: These effects can be mistaken for other conditions like dementia.
• Increased risk of falls: Drowsiness and dizziness are major contributors to falls, a significant health risk for seniors.

Anticholinergic Side Effects: These older antihistamines block acetylcholine, a neurotransmitter important for memory and other bodily functions. Anticholinergic effects are often more pronounced in older adults due to age-related changes.

• Dry mouth and eyes
• Blurred vision
• Constipation
• Difficulty urinating or urinary retention (especially in men with prostate issues)

Dementia Risk: Long-term use of anticholinergic medications, including first-generation antihistamines, has been linked to a higher risk of developing dementia in older adults.

Safer Alternatives for Allergy Relief

For effective and safer allergy relief, second-generation antihistamines are the recommended option for older adults. These drugs are less likely to cross the blood-brain barrier and cause significant sedation or anticholinergic effects.

Recommended second-generation antihistamines include:

• Loratadine: (Claritin, Alavert)
• Cetirizine: (Zyrtec)
• Fexofenadine: (Allegra)

First-Generation vs. Second-Generation Antihistamines

Feature	First-Generation Antihistamines	Second-Generation Antihistamines
Examples	Diphenhydramine (Benadryl), Chlorpheniramine (Chlor-Trimeton), Dimenhydrinate (Dramamine)	Loratadine (Claritin), Cetirizine (Zyrtec), Fexofenadine (Allegra)
Crosses Blood-Brain Barrier?	Yes, easily	No, or very minimally
Sedation	Very common and significant	Minimal to none (Zyrtec can be mildly sedating for some)
Anticholinergic Effects	Common (confusion, dry mouth, urinary retention)	Very rare
Risk of Falls in Elderly	Increased	Lowered
Long-Term Cognitive Risk	Increased risk of dementia with long-term use	Not linked to increased dementia risk

Important Considerations and Non-Drug Alternatives

Before switching any medication, it is vital for older adults to consult with a healthcare professional. A doctor or pharmacist can help select the safest and most effective option, especially for those with existing health conditions like heart disease, glaucoma, or enlarged prostate. The American Academy of Allergy, Asthma, and Immunology also provides guidance for safer allergy management.

Non-medication strategies can also help manage allergy symptoms:

• Use saline nasal sprays to rinse allergens from the nasal passages.
• Keep windows closed during high pollen seasons and use air conditioning with a HEPA filter.
• Take a shower and change clothes after spending time outdoors to remove allergens.

Conclusion

Older adults should be highly cautious of first-generation antihistamines like Benadryl and related products due to the high risk of serious side effects, including confusion, falls, and potential cognitive decline. The safer, modern second-generation antihistamines, such as Claritin, Zyrtec, and Allegra, are the preferred choice for treating allergies in the elderly. Always talk to a healthcare provider to determine the best and safest treatment plan for individual health needs, especially considering potential interactions with other medications.

This information is for educational purposes only and is not a substitute for professional medical advice. Always consult with a qualified healthcare provider regarding any medical conditions or before starting any new treatment.

Frequently Asked Questions

Why is Benadryl not safe for the elderly?

Benadryl, which contains diphenhydramine, is not safe for the elderly because it is a first-generation antihistamine with strong anticholinergic properties. It readily crosses the blood-brain barrier and can cause significant side effects like sedation, confusion, and an increased risk of falls and dementia.

What is the safest allergy medicine for seniors?

The safest oral allergy medicines for seniors are non-sedating, second-generation antihistamines like Claritin (loratadine) and Allegra (fexofenadine), which have minimal central nervous system effects. Zyrtec (cetirizine) is also safe but can cause mild drowsiness in some individuals.

Can elderly people take Zyrtec?

Yes, elderly people can generally take Zyrtec (cetirizine). However, as with any medication in older adults, it's essential to consider individual health factors and consult a healthcare provider, especially if kidney function is a concern.

What are the anticholinergic side effects of antihistamines?

Anticholinergic side effects from first-generation antihistamines include dry mouth, blurred vision, constipation, and urinary retention. These effects are particularly problematic for older adults and can worsen existing conditions like glaucoma and enlarged prostate.

Are older adults at higher risk for side effects from antihistamines?

Yes, older adults are at a higher risk for side effects from first-generation antihistamines because their bodies process and clear drugs more slowly. This makes them more vulnerable to adverse effects like confusion, sedation, and an increased risk of falls.

What if an elderly person needs to take Benadryl for a severe allergic reaction?

In cases of acute, severe allergic reactions, a healthcare provider might determine that the benefits of using a first-generation antihistamine like Benadryl outweigh the risks for short-term use. However, this should only be done under medical supervision. For long-term allergy management, safer alternatives should be used.

Can first-generation antihistamines affect sleep in seniors?

Yes, first-generation antihistamines like diphenhydramine are often used in OTC sleep aids, but they can negatively affect sleep quality in seniors. While they can induce sleepiness, they may reduce restorative REM sleep, leading to feeling unrefreshed. Safer alternatives for sleep issues should be discussed with a doctor.