Can You Take Expired Benadryl?

If you’re feeling a little stuffy or sneezy, taking an expired Benadryl from your medicine cabinet is a temptation. But is it safe? What are the risks?

Most medications retain at least 70 to 80% effectiveness for up to two years after expiration. Expired Benadryl for six months should still work, provided it has been kept in its original container and a cool, dry place away from light. It might not be as effective as before, but there’s very little chance it will cause you any harm.

Read on to know whether or not you can take an expired Benadryl, its safety, what happens when you take it, and other things you need to keep in mind.

Benadryl Expiration Date

can you take expired benadryl

The expiration date of a drug is the last day the manufacturer guarantees full potency and safety. After this date, there’s no assurance that the medication will be effective or safe. 

However, this doesn’t mean that expired drugs are dangerous — it just means they may not work as intended.

For liability and legal reasons, manufacturers cannot guarantee the safety and efficacy of their products beyond the expiration date. The FDA requires companies to place product expiration dates, often conservative estimates.

Drugs are generally considered safe and effective for at least a year after expiration. However, this doesn’t apply to all drugs. Certain medications, such as those that contain high levels of active ingredients, may degrade more quickly after the expiration date.

The implications of taking expired Benadryl are that it may not work as intended and could be dangerous. We should care because taking medication should be done carefully and cautiously to avoid potential risks or consequences.

Shelf Life of Benadryl Products

The average shelf life of Benadryl is two to three years when stored properly. However, this only applies to unopened bottles of medication.

Once you open a bottle of Benadryl, its expiration date will be much shorter because the medication is now exposed to air and light, both of which can degrade its active ingredients over time.

This matters because medication expiration dates are important indicators of a product’s shelf life and potency. Expired medications may not be as effective as they once were, and in some cases, they can even be dangerous. 

Understanding the limitations of expiration dates is essential to ensure you’re taking the safest and most effective course of action regarding your health.

Is It Safe to Take Expired Benadryl?

In general, it’s safe to take expired medications, including Benadryl, if they’re stored properly and have not been damaged.

The active ingredients in most drugs remain stable long after their expiration dates. However, it’s always best to check with a pharmacist or your healthcare provider before taking any expired medication to be sure.

Knowing whether or not you can take expired Benadryl lies in its effectiveness. If you need allergy relief or help to sleep and reach for an expired bottle of Benadryl, you may not get the results you expect because the medication’s potency has decreased over time.

What Will Happen If I Take Expired Benadryl?

If you have expired antihistamines hanging around in your medicine cabinet, they’re probably still effective for up to 3 years.

However, liquid OTC antihistamines should be discarded on their expiration date as they’re more prone to contamination with bacteria or other harmful organisms:

Benadryl Expired 5 Years Ago

It won’t probably cause severe adverse effects, but it’s also not going to be as effective as a newer product. So if possible, try and find something else that can help with your allergies or hives before using a 5-year expired Benadryl medication.

As previously mentioned, Benadryl has a shelf life of 2 to 3 years from when it was manufactured (or opened). So anything older than that should be tossed out rather than used again.

Benadryl Expired 4 Years Ago

Expired Benadryl four years ago isn’t probably going to be harmful if you take it, but the efficacy will have decreased significantly. 

If your allergies are bad, it’s worth getting a new bottle (or checking if generic diphenhydramine is available). However, this isn’t the case with other medications, like tetracycline, which can be harmful if taken after expiration.

So, while taking Benadryl, which expired four years ago, may not be harmful, it also probably won’t do much for your allergies.

Benadryl Expired 3 Years Ago

2 to 4 years after the product’s expiration date is OK. So, an unopened Benadryl that expired three years ago should be fine if you store it properly. If the packaging is opened and the product is exposed to air, it will lose efficacy much sooner.

Benadryl Expired 2 Years Ago

Benadryl expired two years ago and may not function as well as one that hasn’t expired. However, it should still have some usefulness. Benadryl’s effects can continue for a very long period. 

Benadryl Expired 1 Year Ago

One year expired, over-the-counter drugs like Benadryl are safe if stored in a typical “cool, dry” setting. The worst thing that could happen is its effectiveness might be slightly reduced.

Changing over-the-counter (OTC) drugs near their expiration dates is a good idea. However, you can use the stock you already have and then get rid of it after purchasing new stock.

How Does Benadryl Work?

Benadryl is an antihistamine used to treat allergies and common cold symptoms. It’s also used to help you get to sleep if you have trouble falling asleep or staying asleep.

Blocks Histamine

Benadryl works by blocking histamine, a chemical released into the body during an allergic reaction.

Histamine causes symptoms like sneezing, runny nose, itchy throat, or watery eyes. Additionally, it causes swelling of tissues in the nose and throat, making breathing difficult for people with allergies or asthma. 

Blocking histamine prevents these symptoms by reducing inflammation around your nasal passages so they can breathe better without being irritated by allergens like pollen or pet dander that cause reactions when inhaled through the mouth or nose (or absorbed through skin contact).

Diphenhydramine Is Benadryl’s Active Ingredient

The active ingredient in Benadryl is diphenhydramine, which works by blocking histamine receptors in your body. By blocking these receptors, Benadryl stops your immune system from releasing histamines, stopping allergies or cold symptoms.

Not for Anaphylaxis and Other Acute Conditions

Benadryl isn’t meant for acute conditions like asthma attacks or anaphylaxis. It’s for mild conditions like hay fever, hives, or a runny nose.

Side Effects of Benadryl (Expired and Not)

can you take old benadryl

Side Effects of Taking Benadryl

Like with all medications, certain side effects can occur when taking Benadryl. These include:

  • Drowsiness
  • Dizziness or lightheadedness
  • Blurred vision
  • Headache
  • Dry mouth and nose
  • Constipation or stomach upset
  • Skin itching or rash
  • Muscle weakness or pain

Symptoms of a Benadryl Allergic Reaction

But get emergency medical help if you do have signs or symptoms of a Benadryl allergic reaction (whether expired or not):

  • Hives
  • Difficulty breathing
  • Swelling of your face, throat, tongue, or lips

Signs That You Need to Call a Doctor

Also, stop using Benadryl (expired or not) and call your doctor at once if you have any of the following signs and symptoms:

  • Heart palpitations or pounding heartbeats;
  • Difficult or painful urination;
  • Little or no urinating;
  • Confusion;
  • Feeling like you might pass out;
  • Neck or jaw tightness; or
  • Uncontrollable tongue movements.

If you have any of these signs or symptoms while taking Benadryl, contact your doctor as soon as possible.

Again, can you take expired Benadryl? Do not consume expired BENADRYL®. Throw it away, then get a new one.

Benadryl’s Most Common Side Effects

Makes You Sleepy

If you’ve taken Benadryl and felt groggy, it’s due to diphenhydramine, a first-generation antihistamine. This means it also causes drowsiness.

While this might be ideal if you’re already struggling to sleep at night due to your symptoms, the side effects of being drowsy can affect your day-to-day activities.

Note: Some people can take Benadryl without feeling sleepy.

Impairs How You Think and Respond

Benadryl can cause your eyesight to become blurry, and it can also impair your ability to think and respond. So take caution when driving or engaging in activities requiring you to be more alert and see well.

Not Recommended to Take with Alcohol

Drinking alcohol can worsen some of the negative effects of taking diphenhydramine.

It Increases the Risk of Dementia

Benadryl is a common over-the-counter drug that’s been around for decades. While it’s known by many as a mild antihistamine, it’s also an anticholinergic drug. An anticholinergic drug is a medication that blocks acetylcholine’s action in the body. 

Anticholinergic drugs are often prescribed to older adults who have Alzheimer’s disease or dementia because they’re thought to help reduce agitation and confusion.

But recent studies have found that these drugs increase the risk of developing dementia in seniors—and Benadryl is no exception.

published report in JAMA Internal Medicine highlighted that cumulative anticholinergic use, including Benadryl, is associated with an increased risk of developing dementia.

Benadryl Dosage Guide

Benadryl’s dosage is determined by the form of Benadryl you take, what you are trying to treat, and your age. That’s why it’s important to follow the dosage of your medicine bottle carefully.

Below are tables showing the correct Benadryl dosing guide for adults and children:

Benadryl Products for Adults

Benadryl ProductsAgeDosage
Benadryl Allergy 25 mg ULTRATABSUnder six years oldNot recommended
6 to 12 years oldOne tablet every 4-6 hours (or as prescribed by a doctor)
12 years old and older1 to 2 tablets every 4-6 hours (or as prescribed by a doctor)
Benadryl Allergy LIQUI-GELS®Under six years oldNot recommended
6 to 12 years oldOne capsule every 4-6 hours (or as prescribed by a doctor)
12 years old and older1 to 2 capsules every 4-6 hours (or as prescribed by a doctor)
Benadryl Allergy Plus CongestionUnder six years oldNot recommended
6 to 12 years oldOne tablet every 4-6 hours (or as prescribed by a doctor)
12 years old and older1 to 2 tablets every 4-6 hours (or as prescribed by a doctor)

Benadryl Products for Children

Benadryl ProductsAgeDosage
Benadryl Dye-Free Allergy LiquidUnder two years oldNot recommended
2 to 5 years oldNot recommended (unless prescribed by a doctor)
6 to 11 years old1 to 2 teaspoons (5 to 10mL)* every 4-6 hours (or as prescribed by a doctor)
Benadryl Allergy Plus Congestion Oral SolutionUnder four years oldNot recommended
4 to 5 years oldNot recommended (unless prescribed by a doctor)
6 to 11 years oldOne teaspoon (5mL)* every 4-6 hours (or as prescribed by a doctor)
Benadryl ChewablesUnder two years oldNot recommended
2 to 5 years oldNot recommended (unless prescribed by a doctor)
Ages 6 to 11 years old1 to 2 chewable tablets (12.5 to 25mg) every 4-6 hours (or as prescribed by a doctor)
Benadryl Allergy LiquidUnder two years oldNot recommended
2 to 5 years old
Not recommended (unless prescribed by a doctor)
6 to 11 years old1 to 2 teaspoons (5-10mL)* every 4-6 hours (or as prescribed by a doctor)

Note: *tsp = teaspoon mL=milliliter

Benadryl Overdose Information

Before taking any additional medication, including expired Benadryl, for your cough, cold, allergies, or sleep problems, check with your physician or the pharmacist first. 

A lot of medications include antihistamines. Taking a combination of particular products can result in you receiving too much of this medication. Examine the medication’s label to determine whether or not it contains an antihistamine.

Can You Take DayQuil Every 4 Hours?

Frequently Asked Questions – Can Expired Benadryl Still Be Used?

can you still use expired benadryl

Does Benadryl Expire?

Yes, allergy medications like Benadryl will expire eventually. But depending on the type of drug, you may still get some relief after the expiration date has passed. Over-the-counter and prescription antihistamine tablets stay effective longer than liquid medicines, such as corticosteroid nasal sprays.

How Long Is Benadryl Good After Expiration Date?

Antihistamine drugs can still be effective for years after their expiration date. Remember that once you get two or three years past expiration, there’s a higher chance that it’s no longer effective.

Can Expired Allergy Medicine Like Benadryl Hurt You?

Expired medicine can be risky or less effective because of a decrease in strength or change in chemical composition. Also, certain expired medicine is at risk of bacterial growth. And sub-potent antibiotics can fail to treat infections, leading to antibiotic resistance or more serious illnesses. 

Conclusion – Taking Expired Benadryl

Benadryl, over its expiration date, is unlikely to cause you any harm. Also, expired Benadryl has not been linked to any reported adverse effects, nor is there any evidence to suggest that it degrades into anything that could be harmful.

On the other hand, one significant point is that expired Benadryl is not as effective as it once was.

If you are counting on Benadryl to help minimize the symptoms of an allergic reaction, it would be good to have a product that is still “in-date.” This way, you can be sure that the medication will have the potency mentioned on the label and function as intended.

But if you’re still unsure whether expired Benadryl is safe for you, your best bet is to get a new bottle.

Read next:

How Late Can I Take a DayQuil?

When Should You Not Use NyQuil?