Antihistamine Addiction: Definition, Causes, Symptoms, Effects, and Treatment Methods

Antihistamine addiction is a dependency on antihistamines, medications used to relieve allergy symptoms, due to prolonged or excessive use. Antihistamines are safe when used as directed, but some individuals misuse them for sedative effects, which leads to tolerance, dependence, and eventually addiction. Some commonly used antihistamines are Benadryl, Xyrtec, and Allegra.

The causes of antihistamine addiction include self-medication, co-occurring substance use, using higher doses for increased drowsiness, managing sleep issues, social factors, or seeking relaxation. Symptoms of addiction involve increased tolerance, cravings, inability to reduce usage, constant drowsiness, withdrawal symptoms like anxiety or insomnia, and intense desire to use antihistamines.

The effects of long-term antihistamine misuse are memory problems, mental fog, difficulty in urination, headaches, disturbed sleep patterns, and cognitive impairment. Treatment methods for antihistamine addiction are detoxification, gradual tapering, behavioral therapies, counseling, and support groups.

What is Antihistamine Addiction?

Antihistamine addiction is a condition where an individual becomes dependent on antihistamine medications. Antihistamine medications are prescribed drugs to relieve symptoms of allergies, such as itching, sneezing, and runny nose, as highlighted by Khashayar Farzam and Sarah Sabir in their research “Antihistamines” published in the National Library of Medicine.

The researchers stated that there are two primary types of histamine receptors that antihistamines target: H-1 and H-2 receptors. Antihistamines that bind to H-1 receptors are commonly used to relieve symptoms of allergies and allergic rhinitis. H-2 receptors manage upper gastrointestinal issues caused by excess stomach acid.

Antihistamine misuse or addiction occurs when individuals take higher-than-recommended doses for the sedative effects or to manage sleep issues which leads to dependence.

Why is Antihistamine used as medication?

Antihistamines are used as a medication to manage allergic reactions by blocking histamines, which are chemicals released by the immune system during an allergic response. Antihistamines are generally effective and widely recommended by medical professionals. These prescribed drugs relieve symptoms like itching, swelling, nasal congestion, and respiratory discomfort. Antihistamines are essential for individuals with seasonal allergies, asthma, or chronic hives. Antihistamines are prescribed in some cases to manage motion sickness, nausea, and even some forms of anxiety, because of their sedative effects.

How addictive is Antihistamine?

Antihistamines has a high risk of being highly addictive after prolonged or excessive use, especially when used for sedative effects. Individuals who frequently take higher doses develop a tolerance and require increased amounts to achieve the same calming effect, which eventually leads to addiction. Antihistamine addiction or dependence on antihistamines has severe health impacts, such as affecting cognitive function, causing memory issues, and disturbing daily functioning. Chronic use of antihistamines leads to physical and psychological withdrawal symptoms such as insomnia, anxiety, and headaches, making it difficult for people to stop usage without medical support.

How Common is Antihistamine Addiction?

Antihistamine addiction is less common than addiction to opioids or stimulants, but still a concerning condition in the US affecting 6 - 8% of the population. Young adults and teenagers with allergies, skin issues, and sleep disturbances are more prone to antihistamine misuse. Females are slightly more likely than males to misuse over-the-counter antihistamines for sleep aid purposes or anxiety management.

Antihistamines were found in 14.7% (13,574) of 92,033 overdose deaths in the U.S. between 2019 and 2020, with 3.6% (3,345) directly involving antihistamines, according to the study “Notes from the Field: Antihistamine Positivity and Involvement in Drug Overdose Deaths — 44 Jurisdictions, United States, 2019–2020” by Amanda T. Dinwiddie MPH and Lauren J. Tanz, ScD.

The same research highlights that only 0.1% (90 cases) involved antihistamines alone, with nearly all linked to first-generation H1 antihistamines like diphenhydramine. Females made up 52.0% of these cases, particularly in the 35 - 44 age group (26.1%) and White, non-Hispanic individuals (78.1%).

What are the Most Commonly Abused Antihistamines?

The most commonly abused antihistamines are diphenhydramine (benadryl), cetirizine (zyrtec), fexofenadine (allegra), chlorpheniramine (chlor-trimeton), and hydroxyzine (atarax, vistaril).

These antihistamines are described below.

• Diphenhydramine (Benadryl): Diphenhydramine (Benadryl) is a first-generation H1 antihistamine used for allergy relief and as a sleep aid due to its sedative effects. Benadryl’s strong sedative properties increase the risk of misuse.

• Cetirizine (Zyrtec): Cetirizine is a second-generation H1 antihistamine used to treat seasonal allergies and hives without causing strong drowsiness in less quantity. It induces sedation in large doses, making it prone to abuse for sleep or relaxation.

• Fexofenadine (Allegra): Allegra is a non-drowsy, second-generation H1 antihistamine that treats allergy symptoms. It’s less potent and safer from misuse, but people abuse it with other medications, such as Benadryl, morphine, or Zyrtec.

• Chlorpheniramine (Chlor-Trimeton): Chlorpheniramine is a first-generation H1 antihistamine used to treat allergic reactions and cold symptoms. It provides relaxation and drowsiness in high doses.

• Hydroxyzine (Atarax, Vistaril): Hydroxyzine is a prescription-only H1 antihistamine used for anxiety and to increase sedation before surgery. Its strong calming effects make it one of the more commonly abused prescription antihistamines.

What are the Causes of Antihistamine Addiction?

The causes of antihistamine addiction are self-medication, co-occurring substance use, using higher doses for increased drowsiness, managing sleep issues, social factors, or seeking relaxation.

These causes are explained below.

• Self-Medication: Individuals turn to antihistamines to self-treat conditions like itchy skin conditions, anxiety, stress, or mild depression due to their sedative properties. This self-medication further leads to addiction and dependency.

• Co-Occurring Substance Use: People who misuse other substances may combine them with antihistamines to intensify sedation and drowsiness. Combining different drugs increases the risk of addiction to multiple substances, including antihistamines.

• Using Higher Doses for Increased Drowsiness: Using higher doses of antihistamines than recommended increases sedation and drowsiness, making it highly addictive for individuals seeking sleep or high, according to the study titled “Antihistamines” by Theresa A. Zesiewicz and Kelly L. Sullivan, in Handbook of Clinical Neurology, 2011.

• Managing Sleep Issues: Individuals struggling with insomnia misuse antihistamines for their drowsiness effects. Regularly using them as a sleep aid creates a habit that is difficult to break.

• Social Factors: Social factors, such as peer pressure lead some individuals to misuse antihistamines for fun, especially among younger demographics.

• Seeking Relaxation: The calming effects of antihistamines make them attractive for individuals seeking quick relaxation that becomes a habit with frequent use.

What are the Symptoms of Antihistamine Addiction?

The symptoms of antihistamine addiction are increased tolerance, inability to reduce usage, constant drowsiness, withdrawal symptoms, and intense desire to use antihistamines.

These symptoms are explained below.

• Increased Tolerance: Increased tolerance means individuals need higher doses to feel the same sedative effects, as their body is used to the medication, according to the research titled “The development of tolerance to antihistamines” published by the Journal of Allergy and Clinical Immunology.

• Drowsiness: Regular antihistamine use results in excessive drowsiness and people struggle with staying alert which impacts daily functioning and leads to safety concerns, according to the study “Performance effects of antihistamines” by Eli O. Meltzer, MD.

• Inability to Reduce Usage: Individuals with antihistamine addiction face the inability to reduce usage despite making countless attempts to cut back or stop. The behavior indicates a loss of control over their usage.

• Withdrawal Symptoms: Antihistamine users experience symptoms like irritability, anxiety, or sleep disturbances when attempting to stop or reduce intake, as stated in the 2007 study “Chronic diphenhydramine abuse and withdrawal” by Jagroop S Saran 1, Richard L Barbano, and Rachel Schult.

• Intense Desire to Use Antihistamines: An intense desire or craving to use antihistamines, even in non-allergic situations, develops as the individual gets addicted.

What are the Effects of Antihistamine Addiction?

The effects of antihistamine addiction are memory problems, mental fog, difficulty in urination, frequent headaches, disturbed sleep patterns, and cognitive impairment.

These effects are listed below.

• Memory Problems: Prolonged use of antihistamines negatively impacts short-term and long-term memory, according to the 2010 study “Histamine H1 receptor antagonist cetirizine impairs working memory processing speed, but not episodic memory” by P van Ruitenbeek, A Vermeeren, and WJ Riedel. Memory problems make it difficult to remember recent events or learn new information.

• Mental Fog: Individuals with antihistamine addiction experience mental haziness or "brain fog," which can make it challenging to think clearly and respond quickly, according to the news article “Popular antihistamines may cause brain fog” by Joe Graedon and Teresa Graedon.

• Difficulty in Urination: Long-term use of antihistamines interferes with the bladder’s normal functioning and causes issues like urinary retention or difficulty starting and stopping urination, according to the study “The Impact of Pseudoephedrine and Antihistamine on Lower Urinary Tract Symptoms in Male Patients with Rhinitis” by Hsieh, Ming-Li, Shao, I-Hung.

• Frequent Headaches: Frequent headaches occur due to both antihistamine use and withdrawal cycles. These headaches intensify with continued use.

• Disturbed Sleep Patterns: Antihistamines are used to promote sleep but long-term use can disturb sleep patterns. Disturbed sleep patterns lead to dependence on the drug for sleep.

• Cognitive Impairment: Chronic use of antihistamines impairs cognitive functions such as reasoning, problem-solving, and decision-making abilities, according to the 2000 study “The effects of antihistamines on cognition and performance” by Gary G Kay PhD. Cognitive impairment worsens with increased usage and affects personal and professional duties.

What are the Withdrawal Symptoms of Antihistamine Addiction?

The withdrawal symptoms of antihistamine addiction are insomnia, anxiety, vomiting, headaches, sweating, and confusion.

These withdrawal symptoms are listed below.

• Insomnia: Insomnia or difficulty sleeping occurs during withdrawal as the body readjusts to falling asleep without antihistamines.

• Anxiety: Individuals struggling with antihistamine withdrawal experience anxiety attacks when they stop using the drug.

• Vomiting: Vomiting and nausea are frequent antihistamine withdrawal symptoms as the body reacts to the absence of the drug.

• Headaches: Withdrawal from antihistamines cause headaches that last for several days.

• Sweating: Sweating is a physical antihistamine withdrawal symptom linked to stress and discomfort.

• Confusion: Confusion and difficulties in processing information during antihistamine withdrawal occur when the body is craving for the drug.

What are the Treatment Methods for Antihistamine Addiction?

The treatment methods for antihistamine addiction are detoxification, gradual tapering, behavioral therapies, counseling, and support groups.

These treatment methods are described below.

• Detoxification: Detoxification is cleansing the body of antihistamines. Detoxification takes a few days to a week and helps relieve physical symptoms but can be challenging due to withdrawal effects like insomnia or nausea, as stated in the study “Diphenhydramine abuse and detoxification: a brief review and case report” by A. Thomas, DG Nallur and PN Deslandes.

• Gradual Tapering: Gradual tapering is gradually reducing antihistamine dosage over weeks to minimize withdrawal symptoms. Gradual tapering is a gentler approach than detox. Tapering is effective for individuals with mild dependency but takes longer than other methods and requires careful monitoring to prevent relapse.

• Behavioral Therapies: Behavioral therapies such as Cognitive Behavioral Therapy (CBT) address the psychological triggers of antihistamine addiction by changing patterns of thought and behavior. Behavioral therapies are effective but take 3 - 4 months.

• Counseling: Counseling with individual sessions provides a supportive environment for individuals to learn about the emotional and psychological triggers of their antihistamine addiction. Counseling continues for weeks to months and helps recovery by addressing underlying causes.

• Support Groups: Support groups connect people with antihistamine addiction to others experiencing similar struggles. They can share experiences and helpful tips to manage each other’s addiction. Support groups are less structured than formal therapy but provide long-term assistance in preventing relapse.

Who is at risk of Antihistamine Addiction?

People at risk for antihistamine addiction are men and women with a history of substance abuse, or mental health issues, or who use these medications frequently to manage chronic conditions like allergies or sleep disorders. Individuals with a history of substance abuse or mental health issues, such as anxiety or depression, are more vulnerable, as they turn to antihistamines for calming effects or sleep aids. Younger adults and teenagers who experiment with over-the-counter medications are at risk, too, especially if they use these drugs for fun.

How Can You Prevent Antihistamine Addiction Relapse?

You can prevent antihistamine addiction relapse by practicing stress-management techniques, maintaining regular therapy or counseling, and avoiding triggers associated with past use. Stress-management practices like mindfulness, physical activity, and hobbies replace antihistamine use as coping mechanisms for anxiety or sleep difficulties. Consistent therapy sessions help address underlying triggers or mental health concerns. It’s important to identify and avoid triggers linked to previous misuse.

How Does Antihistamine Misuse Compare with Patterns of Other Substance Addictions?

Antihistamine misuse compares with patterns of other substance addictions by leading to tolerance, dependence, and a cycle of compulsive use. Antihistamines are used to cope with anxiety or sleep issues like other addictive substances, such as marijuana and opioids. Antihistamines have milder withdrawal symptoms but the misuse pattern still involves cravings and risk of relapse.

Do antihistamines and opioids act on neurotransmitter systems in the brain?

Yes, both antihistamines and opioids act on the neurotransmitter systems in the brain, but in different ways. Opioids work on opioid receptors and give a rush of dopamine that relieves pain and creates euphoria. Antihistamines, like diphenhydramine, target histamine receptors to create drowsiness and calm, not euphoria. Both substances impact brain chemistry but opioids are much stronger, with a higher risk of opioid addiction and severe withdrawal.

Can individuals use antihistamines to alleviate cravings for marijuana?

Yes, some individuals use antihistamines to alleviate cravings for marijuana as they can offer mild relaxation and drowsiness. However, this isn’t effective because antihistamines don’t fully give marijuana’s effects or help with marijuana addiction withdrawal. Using antihistamines for marijuana cravings will only lead to dependence on antihistamines.