Benadryl For Migraine Management: Does It Work?

At least 39 million Americans¹ suffer from migraines. By choosing the right management techniques, it’s possible to avoid or alleviate key symptoms of this debilitating condition.  

While migraine symptoms may be hard to battle, it doesn’t mean you have to endure them. Many options exist for migraine management. One of them is over-the-counter allergy medications.

Let’s take a closer look at the effectiveness of Benadryl for migraine management.

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What is Benadryl?

Benadryl (active ingredient: diphenhydramine) is an antihistamine medication. It works by blocking two natural substances that your body produces in response to an allergic reaction:

  • Histamine—a chemical that causes allergy symptoms when the immune system tries to get rid of the foreign substance (allergen) that your body comes into contact with;

  • Acetylcholine—a neurotransmitter responsible for many functions, including secretion that causes runny nose and watery eyes.

Benadryl can also block the uptake of serotonin. This can lead to drowsiness and sleepiness. For some conditions, including migraines, this side effect can be positive.  

Usually, doctors prescribe Benadryl to relieve allergy symptoms, such as rash, itching, runny nose, and sneezing. In some cases, Benadryl can be effective for treating the common cold that comes with similar symptoms or preventing and treating nausea and vomiting associated with motion sickness.

Additionally, Benadryl can:

  • Relieve cough that’s caused by minor throat irritation

  • Help with insomnia

  • Control erratic movements in people who are in the early stages of Parkinson’s syndrome

Benadryl can help control and relieve symptoms. However, it can’t treat any of the above conditions.

How does Benadryl help with migraines?

While mostly used to battle allergies, Benadryl can be an effective medication that complements migraine treatment. It can help deal with migraines in different ways, including the following.

Block circulating histamine 

Histamine plays an important role in your body. Battling allergens is just a part of it. Histamine is a molecule that sends messages from one cell to another. For example, it can:

  • Tell your stomach to make stomach acid

  • Help your brain stay awake

  • Regulate memory consolidation (the way your short-term memory turns into long-term memory)

While your body produces histamines naturally, it can also get them from food. Foods that are high in histamine are:

  • Alcohol

  • Pickled or canned food

  • Matured cheeses

  • Beans

  • Chocolate

  • Ready-to-eat meals

  • Salty snacks

If your migraine begins after you eat some of these foods, the trigger might be histamine. Benadryl can block histamine circulation and prevent migraine from occurring. Additionally, by blocking histamine, Benadryl can help calm the nervous system.

Block acetylcholine 

Acetylcholine plays a major role in the way our nervous system works. It’s a key neurotransmitter (messenger) of the autonomic nervous system, which can increase bodily secretions, slow heart rate, dilate blood vessels, and contract smooth muscles. Additionally, it can stimulate or block a nervous system response.

Acetylcholine is also responsible for alertness, memory, thoughts, and judgment.

By blocking acetylcholine, Benadryl creates an effect of drowsiness. Since during a migraine attack, it can be hard to fall asleep, such an effect is welcome. For some migraine sufferers, Benadryl can help get the much-needed rest and recover from an attack faster.

Reduce risks of certain side effects 

When a patient has an acute migraine attack, doctors may consider administering a migraine cocktail. The choice of drugs for the cocktail usually depends on the patient’s medical history and symptoms and may include the following:

  • NSAIDs (nonsteroidal anti-inflammatory drugs) for inflammation and pain reli

  • Acetaminophen for pain relief

  • IV (intravenous) fluids to prevent dehydration

  • Antiemetics to battle nausea and vomiting

  • Dexamethasone to relieve inflammation

To reduce the side effects of some of these drugs, doctors may prescribe Benadryl.

Supplemental medication 

It’s worth noting that Benadryl is a supplemental treatment for migraine. A doctor may suggest taking it together with another medication during an attack. If you go to the emergency room, healthcare professionals may administer Benadryl intravenously.

More research needs to be done to confirm Benadryl’s effect on controlling or alleviating migraine symptoms. In fact, a 2017 study² didn’t show any significant effects of intravenous Benadryl treatment for people with migraines. 

In that study, 40% of people who took Benadryl experienced relief. So did 37% of people who took a placebo.

Acute or preventive?

When doctors prescribe Benadryl, it’s usually for acute treatment. There is no sufficient evidence that antihistamine drugs can help prevent migraines. Accordingly, your doctor isn’t likely to prescribe Benadryl as a preventive measure.

Meanwhile, Benadryl can be effective for acute migraine therapy, both at home and in the ER.

Tolerance for Benadryl 

If you are taking Benadryl on a regular basis, your body may build up a tolerance to the medication.

One study³ found that sleepiness associated with taking Benadryl for the first time went away by day four of regular drug administration.

Another study⁴ demonstrated that patients developed tolerance to antihistamine drugs in general. According to the experiment, it takes between seven and 20 days to develop tolerance to therapeutic doses of antihistamine. The tolerance you build up for one antihistamine drug can extend to others.

You would need to stop taking the drug for three to 14 days for the tolerance to subside.  

If you need to take Benadryl for migraine management, don’t continue using it once the attack is over. Otherwise, you may build up a tolerance. Speak to your doctor about the duration of Benadryl therapy.

Since Benadryl mostly works as acute therapy for migraine attacks, patients rarely take it long enough to develop tolerance.

Benadryl overdose 

Taking too much Benadryl can lead to serious consequences, including heart problems, coma, and death. That’s why it’s important to follow the prescribed dosage. 

The symptoms of Benadryl overdose include:

  • Dilated pupils

  • Dry, red skin

  • Hallucination

  • Inability to urinate

If you decide to take Benadryl without consulting a doctor, make sure to read the label carefully and follow the dosage instructions for your age.

Benadryl and acetaminophen 

Benadryl and acetaminophen are a common combination of drugs. Doctors may suggest using these two medications to treat:

  • Insomnia associated with aches and pains

  • Minor aches and pains

  • Tooth pain

  • Menstrual cramps

  • Runny nose

  • Itchy throat

  • Fever

When you have a migraine, your doctor could prescribe these two drugs to battle both insomnia and headaches that you may experience during the attack.

While you can buy antihistamine (Benadryl) and acetaminophen (Tylenol) separately, some drugs already contain both medications. One of them is Tylenol Severe Allergy.

Side effects

Using Benadryl for migraine management can be effective. However, the medication comes with various side effects. Speak to your doctor about them to avoid worsening your condition during the attack.

Mild side effects of Benadryl 

The majority of people who experience Benadryl side effects face mild discomfort. It includes:

  • Dizziness

  • Drowsiness and sleepiness

  • Loss of coordination

  • Constipation

  • Upset stomach

  • Blurry vision

  • Low blood pressure

  • Headaches

When you take Benadryl for migraine, these side effects can worsen your initial migraine symptoms. If you feel worse after taking Benadryl, make sure to tell your doctor about it.

Serious side effects of Benadryl

Some people can face serious side effects that may land them in an emergency room. While these consequences are rare, your doctor would explain what to do in case they occur.

  • Decreased blood platelets

  • Heart rhythm problems

  • Seizures

  • Hallucination

  • Memory loss

  • Confusion

  • Allergic reactions

If you experience any of the above symptoms, you need to call the doctor immediately. Some of them are easy to confuse with migraine symptoms. The best way to ensure that you are not in any medical danger is to visit an ER.

In general, children and people over 60 who have medical conditions such as liver diseases, kidney problems, heart conditions, or diabetes have a higher risk of developing⁵ side effects.

Since Benadryl isn’t a key migraine management medication, your doctor is likely to cancel it in case you experience any of the side effects.

What to do before taking Benadryl for migraine 

Benadryl is an over-the-counter medication. However, it doesn’t mean you should take it without consulting your doctor first. When you are having a migraine attack, your judgment may be clouded, and you could miss some of the serious side effects.

Before taking Benadryl for migraine, you need to do the following.

Speak to your doctor

Medical history plays an important role in determining whether one can take Benadryl. For example, some people are allergic to its main ingredient, diphenhydramine. Make sure to tell your doctor about allergies to this ingredient or any other antihistamine medications.

Tell your doctor what other drugs you are taking to treat your migraine attacks. Don’t forget to mention both prescription and non-prescriptions meds, including nutritional supplements, herbs, and vitamins.

If you are already using topical antihistamine creams, tell your doctor about them as well.

Share all the conditions you are currently getting treatment for as well as chronic illnesses. Pay special attention to respiratory problems, such as asthma, chronic bronchitis, or emphysema. Benadryl can thicken the mucus in your mouth and nose. This can make breathing harder.

If you are pregnant, planning a pregnancy, or breastfeeding, your doctor may recommend migraine management alternatives.

Consider your age

If you are older than 60, taking Benadryl for migraine management could lead to serious side effects.

Doctors usually don’t prescribe Benadryl to older patients unless they are having severe allergic reactions. There are other complementary medications that can help with migraine management for older adults.

A study⁶ found that administering diphenhydramine to hospitalized patients aged 70 and older led to such consequences as increased risk of cognitive decline.

Stay at home 

One of the main side effects of Benadryl is drowsiness. You need to keep this in mind when planning your activities. Even if Benadryl and other migraine management techniques improve your condition, consider staying at home.

If you need to go somewhere, ask someone to help you. Driving vehicles and operating machinery could be dangerous.

Some people never experience drowsiness after taking Benadryl. Before you know how this medication affects you, try to avoid any activities that require concentration.

Other over-the-counter drugs to treat migraines

Besides Benadryl, several other over-the-counter drugs may be effective during a migraine attack.


When it comes to migraines, pain is the most debilitating symptom. To manage the pain, your doctor is likely to recommend NSAIDs.⁷ They include:

  • Ibuprofen (Motrin, Advil)

  • Acetaminophen (Tylenol)

  • Aspirin (Bayer)

  • Naproxen (Aleve)

All of the above medications, except Tylenol, have both pain-relieving and anti-inflammatory properties. Studies show that when selected properly, NSAIDs can be highly effective for migraine attack management.

Excedrin Migraine

Excedrin is a combination of three active ingredients:

  • Acetaminophen

  • Aspirin

  • Caffeine

All three ingredients can be effective for relieving migraine symptoms. According to a study⁸ of 1,357 people who suffer from migraines, a non-prescription combination of these three ingredients helped alleviate headache pain, nausea, sensitivity to light and sound, and functional disability.

The combination is generally well-tolerated. However, if one of your migraine triggers is caffeine, you should be careful when taking this medication.

While the above meds are available without a prescription, it’s still important to talk to your doctor about taking them. Your physician or neurologist may replace some of the over-the-counter drugs with prescription meds. For example, some doctors recommend Ketorolac for migraine instead of the traditional standard NSAIDs.

The lowdown 

Benadryl is an antihistamine medication that can help alleviate acute migraine attack symptoms. While it can’t treat your migraine, this drug can be highly effective as a complementary management measure.

While you can use Benadryl for migraine without a prescription, contact your doctor for a consultation anyway. They may adjust the dosage or suggest alternatives.

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