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Benadryl addiction: symptoms, effects, withdrawal, and treatment

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Benadryl addiction: symptoms, effects, withdrawal, and treatment

Benadryl addiction involves the compulsive misuse of the antihistamine medication diphenhydramine, leading to increased tolerance, psychological dependence, and withdrawal symptoms upon attempting to reduce or cease its use, driven by the drug’s psychoactive effects.

The symptoms of Benadryl addiction encompass increased drug tolerance, reliance on Benadryl for normal functioning, withdrawal symptoms when not using Benadryl, inability to reduce Benadryl intake, difficulty concentrating and focusing, body weakness, mood swings, drug-seeking behavior, social withdrawal, preoccupation with obtaining the drug, deceptive and secretive behavior.

The effects of Benadryl addiction include both short and long-term effects. The short-term side effects of Benadryl addiction are dry mouth, nose, and throat, dizziness, nausea and vomiting, constipation, and headache. The long-term effects of Benadryl addiction are dementia, anxiety, overdose risk, and psychosis.

The withdrawal symptoms of Benadryl addiction are insomnia, restlessness and irritability, dizziness, headaches, sweating, tachycardia, flu-like symptoms, muscle aches, confusion, and tremors.

The available treatments for Benadryl addiction are detoxification, cognitive-behavioral therapy, medication-assisted treatment (MAT), counseling, inpatient or outpatient rehabilitation treatment, and peer and support groups.

Is Benadryl addictive?

Yes, Benadryl is addictive if taken in excessive amounts or for non-medical reasons. While the risk of addiction to Benadryl is relatively low, it still causes addiction mainly because of the behavioral effects of diphenhydramine, like heightened mood, increased levels of energy, and mild euphoria, as highlighted in Saran JS. et al’s 2017 study, titled “Chronic diphenhydramine abuse and withdrawal: A diagnostic challenge”.

Individuals get addicted to Benadryl when they exceed the recommended frequency or prescribed dosage. If individuals discontinue the use of Benadryl, they undergo withdrawal symptoms, prompting a return to the habit. Over time, this escalates into a complete addiction that necessitates intervention.

Why is using Benadryl addictive?

Using Benadryl is addictive because it induces sedative effects, and creates feelings of relaxation and drowsiness when taken in higher doses or more frequently than recommended. This potential for pleasurable experiences leads individuals to seek out and continue using Benadryl, contributing to the development of tolerance and dependence.

The increased dopaminergic neurotransmission in the mesolimbic pathway, associated with the abuse of antihistamines like diphenhydramine, contributes to the drug’s addictive potential and leads to the development of drug-seeking behavior, as pointed out in the  2017 study, titled “Chronic diphenhydramine abuse and withdrawal: A diagnostic challenge,” published by Neurology Clinical Practice journal.

Diphenhydramine possesses significant antimuscarinic activity, meaning it blocks the action of acetylcholine, a neurotransmitter involved in various bodily functions, as highlighted in the 2021 study by Nemanich A. et al., titled “Increased rates of diphenhydramine overdose, abuse, and misuse in the United States, 2005-2016”. Furthermore, it inhibits the reuptake of serotonin, another neurotransmitter linked to mood regulation. These pharmacological properties contribute to diphenhydramine’s misuse, as individuals seek its sedating and hallucinogenic effects, leading to a pattern of abuse.

What is Benadryl addiction?

Benadryl addiction refers to a state where an individual develops dependence on Benadryl, a brand name for diphenhydramine. According to the 2022 issue of the Journal of Allergy and Clinical Immunology: In Practice, titled “Diphenhydramine: Time to Move on?,” Benadryl was patented and it entered the market in 1946 when medications were not mandated to undergo thorough testing for drug safety or efficacy. Benadryl has been a popular choice for treating various conditions, with widespread recommendations by physicians and pharmacists.

Currently, Benadryl is commonly used to relieve symptoms of allergies, hay fever, common cold, and motion sickness, as well as, promote sleep, and address particular manifestations linked to Parkinson’s disease. Despite its common use, diphenhydramine, the active ingredient in Benadryl, is associated with numerous adverse effects, including severe toxicities and addiction.

Benadryl addiction typically develops when individuals misuse the medication for its sedative effects, seeking relief from issues such as insomnia or allergy symptoms. The availability of Benadryl without a prescription makes it easily accessible, contributing to its potential for misuse and addiction.

What is the other name for Benadryl addiction?

yellow and pink pills

The other name for Benadryl addiction is diphenhydramine abuse. Drug addiction is a worldwide phenomenon, and individuals mostly associate this epidemic with illicit drugs. However, even OTC medications, including diphenhydramine, pose a risk for addiction when misused or abused, as claimed in the 2009 study “Diphenhydramine abuse and detoxification: a brief review and case report,” published in the Journal of Psychopharmacology

Given the unrestricted availability of diphenhydramine, understanding the prevalence of Benadryl addiction helps grasp the scope of the issue and consider appropriate measures for addiction prevention.

How common is Benadryl addiction?

Benadryl addiction is relatively uncommon, but instances of misuse and dependence have been reported, with a 63% increase in intentional diphenhydramine exposures, including Benadryl, within 12 years, as reported in a 2021 study by Nemanich A. et al., titled “Increased rates of diphenhydramine overdose, abuse, and misuse in the United States, 2005-2016,”. The study analyzed data from the US National Poison Data System and revealed that older adults aged 55-64 and ≥65 had around 126-143% and 230% respectively increase in drug misuse. Suicidal incidents associated with diphenhydramine (DPH) were increased particularly among children aged 10-14 (263%). These figures also indicated a rise in major adverse clinical effects by 91% and a 3.6% increase in reported deaths related to diphenhydramine​.

Additionally, in 2020, over 2 million prescriptions were issued for diphenhydramine, including Benadryl, making it the 192nd most commonly prescribed medication in the US, as mentioned in the ClinCalc archive from 2020, titled “The Top 300 of 2020”.

The widespread issuance of prescriptions for diphenhydramine and its variations, such as  Benadryl, indicates its broad applicability. Therefore understanding the symptoms and signs of Benadryl addiction and recognizing the potential consequences associated with its misuse and the impact on individuals’ health is crucial.

What are the symptoms and signs of Benadryl addiction?

The symptoms and signs of Benadryl addiction are listed below.

  • Increased drug tolerance: Needing higher doses of Benadryl over time to achieve the same effects is an indicator of increased drug tolerance. Individuals find that the usual amount of Benadryl becomes less effective, leading to a pattern of escalating use, which contributes to the risk of dependence.
  • Reliance on Benadryl for normal functioning: A reliance on Benadryl for normal functioning goes beyond its intended use and suggests that individuals feel they need the drug to cope with everyday tasks or to feel “normal.”
  • Withdrawal symptoms when not using Benadryl: Experiencing withdrawal symptoms when not using Benadryl, such as insomnia, irritability, and anxiety, indicates physical dependence on the drug. This drives individuals to continue using the drug to avoid these unpleasant symptoms.
  • Inability to reduce Benadryl intake: An inability to reduce Benadryl intake despite the desire to do so is a hallmark of addiction. Individuals struggle to cut down on their use, even if they recognize its negative impact on their health and life.
  • Difficulty concentrating and focusing: Difficulty concentrating and focusing on basic tasks is a result of Benadryl’s sedative effects on the central nervous system, impairing cognitive function. Excessive sedation of Benadryl leads to persistent cognitive difficulties, affecting an individual’s ability to perform everyday mental tasks.
  • Body weakness: Long-term Benadryl use intensifies its sedative effects, leading to drowsiness and general body weakness. This weakness is not a direct effect of the drug but rather an outcome of the sedation it induces, which persists beyond the intended therapeutic duration when misused.
  • Mood swings: Experiencing mood swings is common among individuals struggling with Benadryl addiction. The fluctuations in mood are linked to the drug’s impact on neurotransmitters and emotional regulation.
  • Drug-seeking behavior: A perceived need to take Benadryl for its euphoric effects suggests that individuals are seeking the drug not just for its intended purposes but also for the pleasurable sensations it produces, indicating misuse and potential addiction.
  • Social withdrawal: Individuals who are addicted to Benadryl prioritize its use over social interactions and activities. This leads to a gradual withdrawal from friends, family, and social circles as the individual becomes more preoccupied with obtaining and using the drug.
  • Preoccupation with obtaining the drug: A preoccupation with obtaining the drug is a behavioral sign of addiction, with individuals dedicating significant time and effort to acquiring Benadryl.
  • Deceptive and secretive behavior: Engaging in deceptive and secretive behavior, such as hiding or downplaying Benadryl use, is a common response among individuals struggling with addiction. Such behavior reflects a sense of shame or an attempt to conceal the extent of the problem.

What are the causes of Benadryl addiction?

Benadryl addiction is a complex issue influenced by psychological, social, and environmental factors. The potential causes of Benadryl addiction are listed below.

  • Misuse of psychoactive effects: Individuals misuse Benadryl to experience its psychoactive effects, such as sedation and euphoria, especially in higher doses. Seeking these pleasurable sensations leads to a pattern of misuse and, eventually, addiction.
  • Self-medication: Certain individuals use Benadryl as a form of self-medication to cope with underlying issues such as anxiety, stress, allergies, or sleep disorders. The drug’s sedative properties provide temporary relief, leading to continued use and potential dependence.
  • Ease of access: The over-the-counter availability of Benadryl makes it easily accessible. Its common presence in households and its perceived safety contribute to its misuse, as individuals underestimate the risks associated with excessive use.
  • Drug tolerance: Prolonged use of Benadryl leads to physical dependence, where the body adapts to the presence of the drug. This results in the development of tolerance, contributing to ongoing use. As tolerance increases, individuals face cravings and the risk of addiction due to the need for higher doses to counteract diminished effects.
  • Underlying sleep disorders: People with untreated or undiagnosed sleep disorders are more prone to using Benadryl regularly to manage their sleep difficulties. This increases the risk of dependence.
  • Environmental factors: Social and environmental factors, such as peer influence or a cultural acceptance of substance use, play a role in the development of Benadryl addiction.

What are the effects of Benadryl addiction?

The most prominent effects of Benadryl addiction are drowsiness, dry mouth, nose, and throat, constipation, and blurred vision. All effects of Benadryl addiction are divided into short-term and long-term effects.

The short-term effects of Benadryl addiction are listed below.

  • Dry mouth, nose, and throat: Benadryl’s anticholinergic properties contribute to dryness in the mouth, nose, and throat. This occurs because diphenhydramine, the active ingredient, inhibits the action of acetylcholine, a neurotransmitter responsible for saliva and mucus production.
  • Increased chest congestion: Anticholinergic effects thicken mucus, potentially causing increased chest congestion, especially in individuals prone to respiratory issues.
  • Loss of appetite: Prolonged use of Benadryl leads to a loss of appetite, potentially due to its impact on histamine receptors and neurotransmitter systems that regulate hunger and satiety.
  • Drowsiness: Drowsiness is a common side effect of Benadryl due to its sedative properties. It blocks histamine receptors in the brain, inducing a calming effect and causing drowsiness, especially in higher doses.
  • Dizziness: The sedative effects of Benadryl lead to dizziness as it depresses the central nervous system, impacting balance and coordination.
  • Nausea and vomiting: Benadryl irritates the gastrointestinal lining, leading to nausea and vomiting. This effect is more likely in misuse or ingestion of higher-than-recommended doses.
  • Constipation: Benadryl’s anticholinergic activity disrupts normal bowel function, causing constipation by inhibiting the transmission of signals that stimulate bowel movements.
  • Headache: While the exact mechanism isn’t fully understood, headaches often result from a combination of factors, including changes in blood flow and the impact of Benadryl on neurotransmitter systems.
  • Blurred or double vision: Anticholinergic effects on ocular muscles cause blurred or double vision, affecting visual acuity and potentially causing discomfort.
  • Feeling nervous and excitable: Paradoxically, certain individuals experience feelings of nervousness and excitability as a result of the interplay between the sedative and stimulant effects of Benadryl, particularly during the onset or offset of its action.

The long-term effects of Benadryl addiction are listed below.

  • Dementia: Dementia is a decline in the cognitive function of an individual. Benadryl’s anticholinergic properties interfere with acetylcholine, a neurotransmitter crucial for memory and cognitive functions, contributing to cognitive decline. A 2015 cohort study by JAMA Internal Medicine, titled “Cumulative Use of Strong Anticholinergics and Incident Dementia”, highlighted the association between the widely used anticholinergic drug Benadryl and an elevated risk of dementia.
  • Anxiety: Benadryl’s impact on the balance of neurotransmitters like serotonin and dopamine leads to alterations in mood regulation, potentially contributing to anxiety symptoms with extended use.
  • Overdose risk: The symptoms of Benadryl overdose include restlessness, delirium, confusion, dizziness, agitation, ataxia, tachycardia, dilated pupils, tinnitus, very dry mouth, dry eyes and blurred vision. Prolonged Benadryl addiction further raises the risk of overdose, as higher doses lead to severe and potentially life-threatening complications, including cardiac issues, respiratory failure, rhabdomyolysis, seizures, coma, or even death, as pointed out in StatPearl’s article “Diphenhydramine Toxicity”, updated in April 2023. 
  • Psychosis: The cumulative effects of diphenhydramine on neurotransmitters disrupt mental health, contributing to the development of persistent psychotic symptoms, characterized by impaired reality, hallucinations, and distorted thinking.

Can Benadryl get you high?

A paper with diphenhydramine and a syringe put on it.

Yes, Benadryl can get you high when misused or taken in higher-than-recommended doses. Benadryl has the potential to induce a “high” or altered state of consciousness since its main ingredient, diphenhydramine, possesses sedative and deliriant properties. Consuming large doses of Benadryl results in a state of high that normally lasts for several hours.

Combining alcohol or other substances with diphenhydramine heightens the sensation of being high, leading to feelings of euphoria, hallucinations, and a dissociative state. Abusing Benadryl to achieve a high is dangerous due to its potential to cause severe health risks.In 2020, the US Food and Drug Administration issued a statement, “FDA warns about serious problems with high doses of the allergy medicine diphenhydramine (Benadryl),”  claiming that consuming doses of the widely available over-the-counter allergy medication Benadryl results in severe heart complications, seizures, coma, or potentially fatal outcomes, when exceeded the recommended levels.

What happens if you take a lot of Benadryl?

If you take a lot of Benadryl, it will result in an overdose, leading to severe side effects. According to the 2014 book by Sahand Rahnama-Moghadam et al., titled “Heart and Toxins,” particularly “Chapter 3—Environmental Toxins and the Heart,” the main ingredient of Benadryl—DPH, acts as a relatively non-toxic antagonist for the histamine H1 receptor.

However, with drug abuse, sedative and anticholinergic effects of DPH become pronounced, and fatal outcomes occur within 2 hours of overdose.

The ingestion of diphenhydramine at doses exceeding 1.0 g leads to severe symptoms such as delirium, psychosis, seizures, and coma, as outlined in the Medscape article, titled “Cough, Cold, and Allergy Preparation Toxicity Clinical Presentation,” updated in May 2022.

Moreover, the risk of coma and seizures elevates further with DPH ingestion surpassing 1.5 g, while electrocardiographic disturbances become possible with doses exceeding 3.0 g. Fatalities have been associated with serum DPH concentrations exceeding 5 μg/mL.

Can you overdose on Benadryl?

Yes, you can overdose on Benadryl. An overdose or intoxication with diphenhydramine happens either accidentally or deliberately, as stated in StatPearl’s article “Diphenhydramine Toxicity”, updated in April 2023. Deliberate overdose is associated with individuals attempting self-harm or suicide, while certain individuals intentionally use diphenhydramine to experience pleasurable and euphoric effects.

Overdosing on diphenhydramine presents a range of adverse effects due to its anticholinergic and sedative properties, according to Garry M. Walsh’s 2009 book “Side Effects of Drugs Annual,” “Chapter 15—Antihistamines (H1 receptor antagonists),” an analysis of poisonings between 1992 and 2004 revealed numerous complications, both non-fatal and fatal, associated with diphenhydramine overdose. The study emphasized that diphenhydramine overdose is as dangerous as overdosing on prescription sedatives.

As indicated in the “Diphenhydramine Toxicity” article by David A. Huynh et al., updated in April 2023, 3.2% of drug overdose fatalities in the US were attributed to diphenhydramine overdoses in 2016. Diphenhydramine stood out prominently among the top 15 drugs linked to overdose deaths in the nation, as revealed in the study. Notably, cases of diphenhydramine intoxication or overdose predominantly occurred in children aged 6 years or younger.

What is considered long-term use of Benadryl?

The regular and extended use of the medication is considered long-term use of Benadryl. It typically involves taking Benadryl regularly beyond the recommended or prescribed duration.

Benadryl’s wide availability without a prescription makes it accessible for various purposes, contributing to its long-term use. People often take it for its sedative effects as a sleep aid or allergy relief, but over time Benadryl’s self-administering and prolonged use leads to dependence and reduced effectiveness.

What are Benadryl withdrawal symptoms?

Benadryl withdrawal symptoms vary depending on the duration and intensity of use. While withdrawal symptoms from Benadryl are generally not as severe or well-documented, discontinuing regular use leads to certain unpleasant effects. 

Benadryl withdrawal symptoms are listed below.

  • Insomnia: Discontinuing Benadryl after long-term use leads to difficulty sleeping, characterized by trouble falling asleep or staying asleep, as the body adjusts to the absence of the sedative effects of the drug.
  • Restlessness and irritability: Withdrawal from Benadryl results in a sense of restlessness or irritability, where individuals find it challenging to sit still or experience an overall unease and heightened irritability, becoming easily agitated as they adapt to the absence of the drug’s calming effects.
  • Dizziness: Certain individuals experience dizziness as a withdrawal symptom, potentially leading to feelings of lightheadedness or instability.
  • Headaches: Withdrawal from Benadryl results in headaches, characterized by pain or discomfort in the head, as the body adapts to the absence of the drug.
  • Sweating: During the withdrawal process of Benadryl, the body strives to adapt to the changes in neurotransmitters, leading to symptoms such as increased sweating.
  • Tachycardia: When Benadryl is suddenly discontinued, the absence of the anticholinergic influence leads to an increased release of acetylcholine. This sudden surge in acetylcholine overstimulates the heart, causing an accelerated heart rate or tachycardia as part of the withdrawal process. In a 2017 case study by Saran JS. et al., titled “Chronic diphenhydramine abuse and withdrawal: A diagnostic challenge,” a patient with chronic diphenhydramine abuse exhibited withdrawal symptoms, such as tachycardia and sweating, upon sudden drug discontinuation.
  • Flu-like symptoms (watery eyes, runny nose, etc.): Benadryl, with its antihistaminic properties, suppresses certain immune responses, and upon discontinuation, the immune system reacts, leading to symptoms resembling mild flu, such as watery eyes, a runny nose, and other respiratory discomforts.
  • Muscle aches: Discontinuation of Benadryl results in muscle aches, characterized by discomfort or soreness in the muscles.
  • Confusion: In certain cases, Benadryl withdrawal accompanies confusion, where individuals experience mental fog or difficulty concentrating.
  • Tremors: Withdrawal from Benadryl leads to tremors, characterized by involuntary shaking or trembling of the body.

What are the available treatments for Benadryl addiction?

A picture of detoxification in different colors.

The available treatments for Benadryl addiction are listed below.

  • Detoxification: Detoxification or detox for Benadryl addiction involves the removal of toxins from the body of a patient experiencing acute intoxication and/or dependence on the substance. Typically, detox is followed by comprehensive addiction treatments, which include therapies, counseling, and support groups.
  • Cognitive-behavioral therapy (CBT): CBT addresses the psychological aspects of addiction, helping individuals identify and modify unhealthy thought patterns and behaviors associated with Benadryl use. It aims to foster coping mechanisms and prevent relapse.
  • Medication-assisted treatment (MAT): MAT involves the use of medications to assist in the recovery process from Benadryl addiction. While specific medications for Benadryl addiction are not standard, MAT is tailored to manage co-occurring conditions or symptoms associated with withdrawal.
  • Counseling: Individual and group counseling offers a platform for individuals to share experiences and receive guidance. These sessions foster emotional support, coping strategies, and community throughout the recovery journey.
  • Inpatient and outpatient rehabilitation treatment: Inpatient rehabilitation provides a structured, immersive environment for intensive treatment, while outpatient programs offer flexibility for individuals to receive treatment while maintaining daily life. Both options include therapy, counseling, and education on addiction.
  • Peer support groups: Peer support groups, such as those following the 12-step model, create a community where individuals in recovery from Benadryl addiction share experiences, and encourage and navigate challenges together. These groups emphasize mutual support and accountability.