Is Benadryl Safe After Gastric Sleeve? [Explained]

Antihistamines, including Benadryl (diphenhydramine HCl), are drugs that treat allergies.

This is a question that most people with gastric sleeves are searching for an answer to.

Having said that, let’s find out if is Benadryl safe after gastric sleeve?

Yes, it’s safe for most patients. However, antihistamines like Benadryl should be taken only if a doctor prescribed them. It’s because Benadryl has some long-term side effects to consider. For instance, taking antihistamines for a long can lead to dementia as well as other health complications. 

Do you want the conditions, side effects, and alternatives to Benadryl? Keep reading this article to find out.

How much Benadryl is safe to take might be the first thing you’re asking. Allow me to answer this.

Is Benadryl Safe After Gastric Sleeve?

Benadryl (diphenhydramine) is an antihistamine that’s used to treat allergies and cold symptoms, as well as cough and runny nose. It can make gastric sleeve surgery harder on your stomach. Additionally, it can cause long-term physical and mental side effects. 

You can take Benadryl after gastric sleeve surgery if your doctor says it’s OK, but you should tell your doctor right away if it causes any side effects. Every medicine has a certain recommended amount to prevent side effects. 

Let’s find out the facts about whether Benadryl is good for you or not as we did with caffein and sugar earlier.

How Much Benadryl is Safe to Take?

Like all other medications, Benadryl has different dosages for people of various ages. The dosage for each age group is listed below:

Age GroupDosage
Adults25 to 30 milligrams, every 4 to 6 hours.
12 years old children25 to 30 milligrams, every 4 to 6 hours.
6 to 11 years old children12.5 to 25 milligrams, every 4 to 6 hours.
Below 6 years old childrenAccording to the doctor’s prescribed dosage.

The recommended daily dose for oral Benadryl products is six times max. It is recommended that adults and children over 12 take no more than 300 mg a day. Also, kids between the ages of 6 and 12 are only permitted 150 mg per day. Let’s now examine the negative effects.

What Are the Side Effects of Benadryl?

Benadryl has some side effects, just like other medications. There are common side effects, major side effects, and long-term side effects. Also, side effects in children are concerning. Let’s have a look into the side effects of Benadryl in detail.

Common Side EffectsMajor Side Effects
Drowsiness.Constipation.Weakness.Dizziness.Restlessness.Blurred vision.Urination problem.Swelling nose, throat, or mouth.Seizures.Dry eyes.Trouble breathing.Sleep disturbance.Decrease memory.Severe dizziness.Confusion and impaired thinking.Weakness and muscle twitching.

There are no serious side effects associated with Benadryl. If you experience any of the major side effects, contact your doctor right away.

Long-Term Side Effects

Benadryl isn’t for long-term use that’s why doctors only prescribe it for a short period. There are some long-term side effects of having Benadryl. These are

Side Effects 1: Depression and anxiety

Depression and anxiety can develop in people who take Benadryl regularly. In case of severe depression and anxiety attacks, immediately consult your doctor. 

Side Effect 2: Dementia and memory loss

Dementia is another long-term side effect that commonly happens in people over 65 years old. A study has shown that taking Benadryl for three years or longer has great risk. It causes dementia-like Alzheimer’s disease, confusion, and impaired thinking.

Side Effect 3: Psychosis

Psychosis is a mental disorder that causes delusional thoughts and hallucinations. The patient also faces difficulties in concentration, social interaction, and paranoia. 

Taking Benadryl regularly develops the symptoms of psychosis. People who have psychosis greatly suffer from impaired thinking and lost motivation. In severe cases, psychosis patients are prone to self-harm and suicide. Consult your doctor if you experience any of these symptoms.

Side Effect 4: Decreased blood cells

Having Benadryl on a long-term basis decreases the red blood cells. As a result, it affects the cardiovascular and nervous systems. Decreased red blood cells cause dizziness, heart complications, malnutrition, and kidney failure. 

The condition can progress to anemia or even death in extreme cases.

Side Effect 5: Heart Palpitations

Benadryl can cause a rapid heartbeat if taken regularly. It’s one of the side effects that have long-term effects. The patient can face tachycardia which can result in heart palpitations. If you experience an abnormal heartbeat, make sure to contact your physician right away.

Side Effects In Children

Benadryl can cause unexpected allergic reactions in children. The side effects are given below

  • Drowsiness.
  • Trouble breathing.
  • Seizures.
  • Restlessness.

Which Medications to Avoid After Gastric Sleeve?

There are some medicines that you should avoid after gastric sleeve surgery. These are the following

  • NSAID drugs such as  Naproxen, Celebrex, and Ibuprofen. 
  • Bismuth Subsalicylate.
  • Fiorinal. (Relieves headache)
  • Corticosteroids.
  • Coricidin. (Cold relief for high blood pressure patients.)
  • Aspirins in general.

So, avoid these medications after the surgery to avoid unexpected consequences. Now let’s find out in which cases you should avoid taking Benadryl.

When Should You Avoid Taking Benadryl?

Benadryl is safe to take according to the doctor’s prescribed dosage. However, there are certain conditions when taking Benadryl that can have severe consequences. If you find yourself in such conditions after having gastric sleeve surgery contact a doctor.

The conditions when you should avoid taking Benadryl are given below.

Condition 1: During breastfeeding

Although Benadryl is safe to take during pregnancy it’s not safe during breastfeeding. Breastfeeding can transmit it to kids from infected mothers. So, you should avoid taking Benadryl if you are breastfeeding.

Condition 2: Mixing with Alcohol

Benadryl should never be taken with alcohol. Mixing up antihistamines with alcohol can have fatal consequences. It may result in unconsciousness, memory loss, and even death. Replace alcohol with healthy drinks like a tropical smoothie energizer.

Condition 3: If you Drive Regularly

If you’re regular at driving you should avoid taking Benadryl. It causes drowsiness, dizziness, and weakness. So, it puts you at great risk while driving.

Condition 4: If you have Glaucoma

People who have normal Glaucoma can safely take Benadryl as prescribed. However, people who have a serious condition like “Narrow-angle Glaucoma” should avoid taking antihistamines like Benadryl. It can cause “acute angle closure” or even conditions like dilated pupils.

Condition 5: If You’ve Prostate Or Bladder Problems

Benadryl can cause urinary retention. In case you have prostate problems the condition can get worse with Benadryl. It can interrupt the pelvic muscle by enlarging the prostate gland.

Condition 6: If You Have Dementia

People who have dementia should avoid taking Benadryl completely. It can make the condition worse for patients who already have symptoms of dementia.

Condition 7: If You Have Asthma

You should avoid taking Benadryl if you have asthma. Ingredients in Benadryl can cause the secretions produced in the lung to make it thicker.

Condition 8: Heart disease or hypertension

If you have heart problems and high blood pressure avoids taking Benadryl. It can cause tachycardia and heart palpitations. Some blood pressure supplements not only lower blood pressure but also enhance cardiovascular health.

What are the Alternatives to Benadryl?

Since Benadryl is an antihistamine there are enough alternatives available. There are some alternatives available to Benadryl you can try. However, if you choose to change medications, be sure to consult your doctor first.

The alternatives medicines to Benadryl are given below: 

First Generation AntihistaminesSecond Generation Antihistamines

The Bottom Line

The bottom line is, that Benadryl is an OTC (Over-the-counter) medicine and one of the antihistamines. Post gastric sleeve surgery causes allergic reactions, itching, and swelling. Benadryl is completely safe to use after having a gastric sleeve. It reduces post-surgical allergic reactions and itching. 

Meanwhile, you should also be careful about the conditions we briefly discussed in the article. The symptoms, side effects, and proper dosage should be taken into account with utmost sincerity. Especially after having surgery, you should be careful about taking medicines in general.


Can I take Benadryl for sleep after having surgery?

Benadryl is safe for sleep in post-surgical situations. It will help you relax by making you sleepy. Normally It starts taking action within 20 to 30 minutes after taking it. However, make sure you take the dosage according to the doctor. 

Why does Benadryl make me hyper?

Benadryl can cause a condition called “paradoxical excitation” resulting in hyperactivity and agitation. Because it stimulates the CNS, it has an impact on it. In this case, you should consult with a doctor asap to change the medication.

When do antihistamines not work?

If there’s no histamine reaction in the body there will be no antihistamine effect as well. For some people, first-generation antihistamines don’t work. They become immune to the first gen and can benefit from second-generation antihistamines.


That should clear out your doubts on “ is Benadryl Safe after Gastric Sleeve?”.

Benadryl works effectively against post-surgical itch. It’s completely safe to use after having gastric sleeve surgery. However, you should only take it according to the doctor’s recommended dosage. 

Bye for now! We’ll meet you at the next one. Till then stay healthy.

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