How much Benadryl is safe to take. What are the recommended dosages for adults and children. Can Benadryl be dangerous if misused. What are the potential side effects and risks of Benadryl overdose.

Understanding Benadryl: An Overview of the Popular Antihistamine

Benadryl is a well-known over-the-counter antihistamine medication used to combat allergy symptoms and mild cold discomfort. The active ingredient, diphenhydramine, works by counteracting the effects of histamine, a substance produced by the body in response to allergens. While Benadryl is widely available without a prescription, it’s crucial to understand its proper use and potential risks.

What does Benadryl treat?

Benadryl is primarily used to alleviate symptoms such as:

• Sneezing
• Itchy eyes
• Scratchy sensations in the nose or throat
• Runny nose
• Difficulty breathing due to allergies

Some individuals also use Benadryl to manage similar symptoms associated with the common cold.

Safe Dosage Guidelines for Benadryl

Proper dosing is essential for the safe and effective use of Benadryl. The standard dosage varies between adults and children, and it’s crucial to follow the instructions provided on the packaging.

What is the recommended Benadryl dosage for adults?

For adults, the standard dose of diphenhydramine in brand name Benadryl is 25 mg per dose. It’s important to note that this dosage should not be exceeded without consulting a healthcare professional.

How much Benadryl is safe for children?

Children’s formulas of Benadryl typically contain 12.5 mg of diphenhydramine per dose. However, it’s crucial to consult with a pediatrician before administering Benadryl to children, especially those under 12 years old, as they metabolize the medication more slowly.

Factors Affecting Benadryl Metabolism and Elimination

Several factors can influence how quickly Benadryl is processed and eliminated from the body. Understanding these factors is crucial for safe usage.

How long does Benadryl stay in the system?

For the average healthy adult, the elimination half-life of Benadryl ranges from 6.7 to 11.7 hours. This means that between 6 to 12 hours after taking Benadryl, half of the drug will be eliminated from the body. Within approximately two days, the drug should be completely cleared from the system.

However, various factors can affect this timeline:

1. Age: Older adults (over 65) and young children metabolize diphenhydramine more slowly.
2. Liver function: The liver plays a crucial role in processing Benadryl, so individuals with liver problems may have difficulty metabolizing the drug safely.
3. Kidney function: Decreased renal function can impact the body’s ability to eliminate Benadryl.
4. Hydration levels: Proper hydration is essential for efficient drug elimination.
5. Dosage: Higher doses or prolonged use can lead to slower metabolism and potential drug buildup.
6. Drug interactions: Other medications can affect how the body processes Benadryl.
7. Body composition: An individual’s weight and body mass can influence drug metabolism rates.

Potential Side Effects of Benadryl Use

Even when taken as directed, Benadryl can cause various side effects. It’s important to be aware of these potential reactions.

What are the common side effects of Benadryl?

Common side effects of Benadryl may include:

• Drowsiness or sleepiness
• Dry mouth
• Dryness in the nose or throat
• Dizziness
• Nausea or stomach upset
• Headaches
• Jitteriness or restlessness
• Tightness in the chest
• Muscle weakness
• Loss of appetite
• Constipation

These effects typically peak around two hours after consumption and generally subside within four hours. However, it’s crucial to allow sufficient time for the drug to be fully metabolized before taking another dose.

The Dangers of Benadryl Misuse

While Benadryl is readily available over the counter, misuse can lead to serious health risks. It’s essential to understand the potential dangers associated with improper use of this medication.

Can you get high on Benadryl?

Some individuals may attempt to use Benadryl recreationally due to its sedative effects. However, taking more than the recommended dose in an attempt to achieve a “high” is extremely dangerous and can lead to severe health consequences. The risks far outweigh any potential euphoric effects.

What are the risks of Benadryl overdose?

Taking excessive amounts of Benadryl can result in an overdose, which can be life-threatening. Symptoms of Benadryl overdose may include:

• Severe drowsiness
• Confusion
• Blurred vision
• Rapid heartbeat
• Seizures
• Difficulty urinating
• Hallucinations
• Agitation
• Coma

If you suspect a Benadryl overdose, seek immediate medical attention.

Safe Usage and Precautions

To ensure safe use of Benadryl, it’s crucial to follow recommended guidelines and take necessary precautions.

How can Benadryl be used safely?

To use Benadryl safely:

1. Always follow the recommended dosage instructions on the package.
2. Do not exceed the maximum daily dose.
3. Avoid using Benadryl for extended periods without consulting a healthcare professional.
4. Be aware of potential drug interactions with other medications you may be taking.
5. Do not mix Benadryl with alcohol or other substances that cause drowsiness.
6. Use caution when operating machinery or driving, as Benadryl can cause drowsiness.
7. If symptoms persist or worsen, consult a healthcare provider.

Are there any special considerations for certain groups?

Certain individuals should exercise extra caution when using Benadryl:

• Elderly adults: May be more sensitive to side effects and should consider lower doses.
• Children: Dosage should be carefully calculated based on weight and age. Always consult a pediatrician.
• Pregnant or breastfeeding women: Should consult their healthcare provider before using Benadryl.
• Individuals with certain medical conditions: Those with liver or kidney problems, glaucoma, or urinary retention should consult a doctor before use.

Alternatives to Benadryl

While Benadryl can be effective for managing allergy symptoms, there are alternative options available for those who may be concerned about its side effects or potential for misuse.

What are some alternatives to Benadryl for allergy relief?

Several alternatives to Benadryl exist for managing allergy symptoms:

1. Second-generation antihistamines: These include medications like cetirizine (Zyrtec), loratadine (Claritin), and fexofenadine (Allegra). They tend to cause less drowsiness than Benadryl.
2. Nasal corticosteroids: Medications like fluticasone (Flonase) and mometasone (Nasonex) can effectively manage nasal allergy symptoms.
3. Eye drops: For allergy-related eye symptoms, antihistamine eye drops may provide relief.
4. Natural remedies: Some individuals find relief through natural approaches such as saline nasal rinses, local honey consumption, or herbal supplements like butterbur.
5. Immunotherapy: For severe or persistent allergies, allergen immunotherapy (allergy shots or sublingual tablets) may be recommended by an allergist.

Always consult with a healthcare provider to determine the most appropriate treatment option for your specific situation.

Recognizing and Addressing Benadryl Dependence

While Benadryl is not typically considered addictive in the traditional sense, regular use can lead to psychological dependence or habituation. It’s important to be aware of the signs of overreliance on this medication.

Can you become dependent on Benadryl?

While Benadryl does not cause physical addiction, some individuals may develop a psychological dependence on its sedative effects, particularly if used as a sleep aid. Signs of potential dependence include:

• Using Benadryl more frequently than recommended
• Feeling unable to sleep without taking Benadryl
• Experiencing anxiety when Benadryl is not available
• Continuing to use Benadryl despite negative side effects
• Neglecting other methods of managing allergies or sleep issues

How can Benadryl dependence be addressed?

If you suspect you’ve developed a dependence on Benadryl, consider the following steps:

1. Consult a healthcare provider: They can assess your situation and provide guidance on safely reducing Benadryl use.
2. Explore alternative treatments: Work with your doctor to find other methods for managing your allergy symptoms or sleep issues.
3. Gradually reduce usage: Under medical supervision, slowly decrease your Benadryl intake to minimize potential withdrawal effects.
4. Address underlying issues: If using Benadryl for sleep, consider cognitive behavioral therapy for insomnia or other sleep hygiene improvements.
5. Seek support: Consider joining a support group or speaking with a therapist to address any psychological aspects of dependence.

Remember, it’s essential to approach any change in medication use under the guidance of a healthcare professional to ensure safety and effectiveness.

The Future of Antihistamine Research and Development

As our understanding of allergies and histamine responses evolves, so too does the field of antihistamine medications. Researchers continue to explore new ways to manage allergy symptoms more effectively and with fewer side effects.

What advancements are being made in antihistamine medications?

Several areas of research are promising for the future of allergy treatment:

• Targeted delivery systems: Researchers are developing methods to deliver antihistamines more precisely to affected areas, potentially reducing systemic side effects.
• Combination therapies: New medications that combine antihistamines with other anti-inflammatory agents are being studied for enhanced efficacy.
• Long-acting formulations: Extended-release versions of antihistamines could provide longer-lasting relief with fewer doses.
• Novel mechanisms: Scientists are investigating new ways to block histamine receptors or prevent histamine release altogether.
• Personalized medicine: Genetic research may lead to more tailored antihistamine treatments based on individual patient profiles.

These advancements could potentially offer safer and more effective alternatives to traditional antihistamines like Benadryl in the future.

How might future developments impact the use of Benadryl?

As new antihistamine medications are developed, the role of Benadryl in allergy treatment may evolve:

1. Reduced reliance: Newer, more targeted treatments may decrease the need for first-generation antihistamines like Benadryl.
2. Specialized use: Benadryl may become more focused on specific applications where its sedative effects are beneficial.
3. Improved formulations: The Benadryl formula itself might be updated to reduce side effects or enhance efficacy.
4. Combination products: Benadryl might be incorporated into new combination medications that address multiple symptoms simultaneously.
5. Over-the-counter status: Regulations around the availability of Benadryl and similar medications may change based on new research findings.

While Benadryl remains a valuable tool in managing allergy symptoms, staying informed about new developments in antihistamine research can help individuals make the best choices for their health in consultation with healthcare providers.

Getting High on Benadryl: How Much Is Safe?

Benadryl is a brand name over-the-counter antihistamine medication. Histamine is a substance produced by the body in response to the presence of allergens like pollen, animal hair, or dust. Histamine release underlies certain symptoms like sneezing, itchy eyes, scratchy feelings in the nose or throat, runny nose, and difficulty breathing. Antihistamines like Benadryl combat the actions of histamine. Some people may also take Benadryl to reduce similar symptoms when they have a cold. Diphenhydramine is the main ingredient in this drug, and the substance can be found in other over-the-counter medications, too.¹

Although Benadryl is sold without a prescription, the drug can cause drowsiness and sedation. Misuse of the medication may occur because people do not properly read the directions, mix it with alcohol or other intoxicants, or take too much of it at once. Any form of misuse can be dangerous and may result in severe side effects or an overdose. ¹

Just like with a prescription drug, it is important to follow the instructions on the package and only take Benadryl in recommended doses for a short period of time.

What Is Benadryl? How Is It Taken Safely?

Benadryl was the first antihistamine to receive approval from the Food and Drug Administration (FDA). The brand name was acquired by Johnson & Johnson in 2007 and the medication remains a widely-used treatment for allergies and mild cold symptoms.¹

Since the medication has been available for several decades, safe dosage and elimination time are well understood. Benadryl is available in a variety of formulations, including tablets, liquid gels, and chewables. The standard dose of diphenhydramine in brand name Benadryl is 25 mg per dose for adults and 12.5 mg per dose in children’s formulas. For the average healthy adult, elimination half-life ranges from 6.7 to 11.7 hours.² So between 6 to 12 hours after taking Benadryl, half the drug will be eliminated from the body. Within two days, the drug will be completely gone from the body.

Several factors impact how quickly Benadryl is metabolized, including: 3

• Age: Adults over 65 years old and children younger than 12 years old metabolize diphenhydramine more slowly, so lower doses less often are safer.³
• Liver problems: Since the active ingredient in Benadryl is processed through the liver, anyone with decreased hepatic function will have difficulty safely consuming this drug.
• Kidney problems: The kidneys help to process toxins by passing them out through the bladder. People who have decreased renal function may have a tough time metabolizing Benadryl. Urinary pH can also impact how the body processes diphenhydramine.
• Hydration: People who do not drink sufficient water may struggle to eliminate diphenhydramine from their system.
• Low vs. high dose: Even healthy adults who take more than the recommended dose of Benadryl will experience consequences, such as taking longer to metabolize the drug. Taking the recommended dose of Benadryl for longer than recommended may also lead to tolerance as the drug builds up in the body, and that also might increase the medication’s elimination time.
• Other medications: Taking prescription drugs, or other over the counter drugs, along with Benadryl may change how the body metabolizes all the substances together.
• Body weight/mass: Different body types process different amounts of medication at different rates. This is true for prescription drugs, recreational substances like alcohol, and over the counter drugs like Benadryl.

Although Benadryl is sold over the counter without a prescription, the active ingredient is potent and has an impact on the body. In addition to eliminating symptoms of allergies or a cold, it also interacts with other organ systems.

Even when taken as directed, Benadryl can cause side effects which include: 4

• Drowsiness or sleepiness.
• Dry mouth.
• Dryness in the nose or throat.
• Dizziness.
• Nausea or stomach upset.
• Headaches.
• Jitteriness or restlessness.
• Tightness in the chest.
• Muscle weakness.
• Loss of appetite.
• Constipation.

When the recommended amount is consumed, effects peak after about two hours. Within four hours, most effects of the medication wear off. There are still metabolites from diphenhydramine’s breakdown in the body, so taking another dose of Benadryl before the full effects wear off may be dangerous.⁵

Additionally, some people take more than the recommended amount because they want to get high. Benadryl produces mild sedative effects, and in larger amounts, that can feel like intoxication.

However, taking more than 25 mg can be extremely dangerous and is more likely to cause harm than produce any euphoria. ⁵

Benadryl Overdose

Too much Benadryl can lead to an overdose and taking the drug with other potent substances can increase the risk of overdose.

For example, taking other antihistamines that contain diphenhydramine can lead to an overdose. Substances like alcohol or benzodiazepines (e.g., Valium, Xanax, Klonopin, etc.) may dangerously increase Benadryl’s sedative effects.

Muscle relaxants, sedative-hypnotic sleep medications like Ambien, tranquilizers, opioids, and other prescription drugs that are central nervous system (CNS) depressants can also adversely interact with Benadryl. In addition, some types of antidepressants called monoamine oxidase inhibitors (MAOIs) do not mix with antihistamines like Benadryl.³

Symptoms of a Benadryl overdose include: 6

• Enlarged pupils.
• Very dry eyes.
• Blurry vision.
• Ringing in the ears (tinnitus).
• Low blood pressure.
• Rapid heart rate.
• Agitation, rapid mood swings, or restlessness.
• Confusion.
• Seizures.
• Delirium.
• Intense, sudden depression.
• Extreme drowsiness.
• Passing out or falling asleep.
• Nervousness or paranoia.
• Physical tremors.
• Unsteady gait, loss of balance, or inability to walk.
• Dry, red skin.
• Nausea or vomiting.
• Inability to urinate.

Attempting to Get High on Benadryl Can Be Extremely Dangerous

Benadryl is not effective as an intoxicant.Taking more than the recommended dose is more likely to lead to an overdose and uncomfortable side effects rather than euphoria. More than 500 mg, which is more than 40 times the recommended dose, may lead to a state of delirium, hallucinations, and other overdose symptoms. Anecdotal evidence about diphenhydramine highs indicates that the effects are more often uncomfortable and unsettling instead of enjoyable.

Attempts at getting high on Benadryl may be indicative of larger issues with addiction or substance abuse. Because Benadryl is easy to acquire, it may be the first drug abused by an adolescent, or it could be a drug abused after struggling with other substances. Regardless, it is important to get help ending substance abuse.

There are many risks in taking Benadryl long term, or mixing it with another drug or medication. If you have been abusing the prescribed dosage for Benadryl, it’s important to be informed about other potential signs that could lead to addiction.

If you or someone you love is struggling with substance abuse issues and are unsure of where to turn, call us today at . River Oaks, one of American Addiction Centers’ Florida rehab centers, is ready to help you overcome addiction and find long-term recovery. Call us today at to learn more about addiction treatment near you.

You aren’t alone. You deserve to get help.

We are here to help you get sober and learn how to stay that way. Retreat to the sunny climate near Tampa, Florida for a stay at the gold standard of treatment facilities. At River Oaks, we offer customized care plans to help you on your recovery journey at our beautiful Hillsborough County campus.

What is the max dose of diphenhydramine for adults?

Medically reviewed by Carmen Pope, BPharm. Last updated on Oct 4, 2021.

I took two 50mg capsules thinking they were 25mg each (that is I took 100mg instead of 50mg) and it was the only thing that put me into a nice 6 hour sleep which I have not had for weeks! If it is acceptable I will try to take this to finally get some good sleep!

The maximum oral dose of diphenhydramine for adults is generally reported as 100mg for a single dose or no more than 300mg in 24 hours, but this can vary depending on what condition diphenhydramine is being used for, the salt of diphenhydramine used (there are two salts available in the United States, diphenhydramine citrate and diphenhydramine chloride), the age of the person, how much diphenhydramine they have tolerated before, and if they are on any interacting medications. Taking too much diphenhydramine can be fatal.

Diphenhydramine is one of the most abused medications in the United States and a 2016 study found that diphenhydramine overdosage accounted for 3.2% of all overdosage deaths in the United States and ranked among the top 15 drugs most frequently involved in drug overdose deaths in the United States. Most diphenhydramine intoxication/overdose cases occur in children ages 6 years or younger. Children who have taken or been given more than 7.5mg/kg of diphenhydramine should be taken to a healthcare facility for observation because they require medical supervision and management. Diphenhydramine overdose or intoxication can be either accidental or intentional.

What is the maximum dose of diphenhydramine for sleep?

When used as a sleep aid the maximum recommended dosage is 76mg for diphenhydramine citrate or 50mg for diphenhydramine hydrochloride. Although diphenhydramine is commonly used for sleeping it is not recommended because it prevents the brain from achieving restorative deep REM sleep and tends to cause anxiety or a “hangover” effect, which causes a person to feel drowsy the next day. Alternatives, such as zolpidem, are preferred as a sleep aid.

Taking diphenhydramine as a sleep aid for more than 7 to 10 nights is not recommended, because you will gain tolerance to it.

Diphenhydramine should never be given to children to help them sleep and is best not given to children younger than 12 years of age without the direction of a physician. Use in children under 6 years old should be avoided. Long-acting tablets or capsules should never be given to children.

What are the symptoms of diphenhydramine overdose or toxicity?

Diphenhydramine can be harmful in large amounts. Symptoms of a diphenhydramine overdose include:

• Blurred vision
• Confusion
• Dry mouth
• Dry skin
• Drowsiness
• Hallucinations (seeing or hearing things that aren’t there)
• Heart rhythm disturbances such as QT prolongation
• Nausea and/or vomiting
• Nervousness
• Psychosis
• Seizures
• Sleepiness
• Tremor
• Unsteadiness.

Recovery from a diphenhydramine overdose is likely if the person survives the first 24 hours but in some people, serious heart rhythm disturbances may occur, which can cause death.

What medicines contain diphenhydramine?

Diphenhydramine may be found in many medicines, sometimes in combination with other ingredients such as acetaminophen or ibuprofen, for example:

• Advil PM
• Aleve PM
• Bayer PM
• Benadryl
• Dimetapp
• Ivarest
• Nytol
• Sominex
• Tylenol PM
• Unisom.

What brands contain diphenhydramine hydrochloride and diphenhydramine citrate?

Common brands containing diphenhydramine and the salt they contain include:

• Advil PM (diphenhydramine citrate)
• Aleve PM (diphenhydramine hydrochloride)
• Bayer PM (diphenhydramine citrate)
• Benadryl (diphenhydramine hydrochloride)
• Dimetapp (diphenhydramine hydrochloride)
• Ivarest (diphenhydramine hydrochloride)
• Sominex (diphenhydramine hydrochloride)
• Tylenol PM (diphenhydramine hydrochloride)
• Unisom (diphenhydramine hydrochloride).

References

• Diphenhydramine overdose Mt Sinai.https://www.mountsinai.org/health-library/poison/diphenhydramine-overdose
• Huynh DA, Abbas M, Dabaja A. Diphenhydramine Toxicity. [Updated 2021 May 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK557578/
• Zhang D, Tashiro M, Shibuya K, Okamura N, Funaki Y, Yoshikawa T, Kato M, Yanai K. Next-day residual sedative effect after nighttime administration of an over-the-counter antihistamine sleep aid, diphenhydramine, measured by positron emission tomography. J Clin Psychopharmacol. 2010 Dec;30(6):694-701. doi: 10.1097/jcp.0b013e3181fa8526. PMID: 21105284.
• Katayose Y, Aritake S, Kitamura S, Enomoto M, Hida A, Takahashi K, Mishima K. Carryover effect on next-day sleepiness and psychomotor performance of nighttime administered antihistaminic drugs: a randomized controlled trial. Hum Psychopharmacol. 2012 Jul;27(4):428-36. doi: 10.1002/hup.2244. PMID: 22806823.

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Medical Disclaimer

Quick Answer: How much Benadryl is safe for a dog?

According to the Merck Veterinary Manual, the safe dosage is 2-4 milligrams per kilogram of body weight, or 0. 9 to 1.8 milligrams per pound. This amount can be administered two to three times a day, depending on your dog’s symptoms.

Benadryl is commonly used to treat itching in dogs caused by skin allergies and also reduces many other allergy symptoms, including: hives. Edema and inflammation. Redness.

With proper pet safety instructions, proper dosage, and guidance from your veterinarian, yes, Benadryl can be safe for dogs. With all medications, please observe your dog’s behavior during the first medication trial. Before proceeding, make sure your dog is not reacting abnormally to the medication.

Benadryl may cause severe drowsiness, dry mouth or urinary retention in the dog, and potentially cause gastrointestinal disturbances such as diarrhea and/or vomiting.

According to the Merck Veterinary Manual, the safe dosage is 2-4 milligrams per kilogram of body weight, or 0.9 to 1.8 milligrams per pound. This amount can be administered two to three times a day, depending on your dog’s symptoms.

This medicine will work quickly, in about 1-2 hours, and this should be followed by an improvement in clinical signs.

Oatmeal is an age old remedy for dry, itchy skin that is safe to use on our dog friends too! In fact, most hypoallergenic dog shampoos contain oatmeal as an active ingredient that soothes and fights irritation. Start by grinding plain oatmeal into a powder to sprinkle in your dog’s warm bath.

When dog scratches get out of hand, it’s often the result of food allergies or environmental factors, including mold and pollen. Dogs can also develop a skin irritation called contact dermatitis when in contact with substances such as pesticides or soaps. Boredom or anxiety.

The standard dose of oral Benadryl for dogs is 1 mg per pound of body weight 2-3 times daily. Most diphenhydramine tablets have a 25mg dose, which is about the size of a 25-pound dog. But the safest way to give the correct dose is to ask your veterinarian.

Never give your dog too much Benadryl – an overdose is possible. Abuse of the drug can lead to fatal diphenhydramine poisoning, so always consult your veterinarian if you are unsure of the correct dosage. Signs of an overdose include constipation, agitation, dilated pupils, seizures, and rapid heartbeat.

Diphenhydramine-only Benadryl is a human drug that can also be used as an additional labeling drug for dogs. It is very important to check the ingredients on the label as some strains contain additional ingredients such as phenylephrine that may be harmful to your pet.

You can give your dog Benadryl (diphenhydramine) 2-3 times a day at a rate of 1 mg per pound of body weight. For example, a 12-pound dog may receive 12 mg, which is equal to one child’s dose of Benadryl or ½ an adult’s dose. A 50 lb dog will need 50mg or two of adult Benadryl. Benadryl may cause drowsiness.

Benadryl begins to work in 15-30 minutes, and its maximum effect occurs in 2-4 hours. The adult dose for sedation is 25 to 50 milligrams.

It is true that Benadryl can relieve symptoms in some dogs, but the sedative effects are mild and not as pronounced in dogs as they are in humans. Thus, in general, Benadryl does not usually help dogs struggling with anxiety or phobias.

Antihistamines. Diphenhydramine (Benadryl®), cetirizine (Zyrtec®), and loratadine (Claritin®) are commonly antihistamines that relieve allergy symptoms or counter allergic reactions. Antihistamines are generally safe, but they can cause drowsiness in some dogs and hyperactivity in others.

Is expired Benadryl safe?

If a medicine is past its expiration date, throw it away and replace it with a new product, Benadryl says. However, according to The Allergy Clinic.

The expiration date on medicine vials is the last date the manufacturer is prepared to guarantee safety and efficacy. After the expiration date, nothing happens for the drug to lose its effectiveness, explains the Harvard Medical School Family Health Guide. Many medicines, especially those kept in unopened original containers, can remain effective for many years after the expiration date.