How do antihistamines affect body weight. What are the mechanisms behind antihistamine-induced weight gain. Which antihistamines are most likely to cause weight gain. What are alternative allergy treatments that don’t contribute to weight gain. How can allergy sufferers manage their symptoms without risking weight gain.

The Link Between Antihistamines and Weight Gain

Allergy sufferers often turn to antihistamines for relief, but recent research suggests these medications may have an unexpected side effect: weight gain. A 2010 study published in the journal Obesity by scientists from Yale University found that people who took antihistamines were more likely to gain weight. This finding has significant implications for the millions who rely on these medications to manage their allergy symptoms.

The connection between antihistamines and weight gain is rooted in the complex interplay between histamine and our body’s metabolic processes. Histamine, a chemical involved in the immune response, also plays a role in regulating appetite and metabolism.

How Antihistamines Affect Appetite and Metabolism

Antihistamines work by blocking histamine receptors, including those in the hypothalamus, the brain’s appetite control center. When these receptors are blocked, several physiological changes occur:

• The brain may not receive proper “fullness” signals, leading to increased appetite and overeating
• The body’s ability to burn calories efficiently is reduced, resulting in a slower metabolism
• Fat breakdown processes may be impaired
• Some antihistamines can cause fatigue, potentially reducing motivation to exercise

These factors combined can create a perfect storm for weight gain, especially if antihistamines are used regularly over extended periods.

Antihistamines Most Likely to Cause Weight Gain

Not all antihistamines are created equal when it comes to their potential impact on weight. Some medications are more likely to cross the blood-brain barrier and affect the hypothalamus, increasing the risk of weight gain. The following antihistamines have been associated with an increased likelihood of weight gain:

• Diphenhydramine (Benadryl and others)
• Cetirizine (Zyrtec)
• Levocetirizine (Xyzal)
• Fexofenadine (Allegra)
• Hydroxyzine (Atarax, Vistaril)
• Chlorpheniramine maleate (Chlor-Trimeton)

Is there an antihistamine that doesn’t cause weight gain? Loratadine (Claritin) appears to be the best option for those concerned about weight gain. This medication doesn’t cross into the brain as readily as other antihistamines, making it less likely to stimulate appetite or cause fatigue.

Other Side Effects of Antihistamines

While weight gain is a significant concern, it’s important to be aware of other potential side effects associated with antihistamine use. These may include:

• Dry mouth
• Drowsiness
• Dizziness
• Nausea and vomiting
• Restlessness or moodiness
• Urinary retention
• Blurred vision
• Confusion

These side effects can vary in severity and frequency depending on the specific antihistamine and individual factors. It’s always advisable to consult with a healthcare provider about potential side effects and drug interactions before starting any new medication.

Alternative Allergy Treatments

For those concerned about the potential weight gain associated with antihistamines, several alternative treatments can help manage allergy symptoms without this risk. These options include:

1. Steroid nasal sprays
2. Eye drops
3. Decongestants
4. Cromolyn sodium nasal spray
5. Allergy shots (immunotherapy)

Additionally, non-pharmaceutical approaches can be effective in managing allergy symptoms:

• Frequent showers to remove pollen and other allergens
• Salt-water nasal washes to clear nasal passages
• Reducing exposure to known allergy triggers (pollen, dust, mold, pet dander)
• Using air purifiers in the home
• Keeping windows closed during high pollen count days

The Obesity-Allergy Connection

Interestingly, research suggests a bidirectional relationship between obesity and allergies. Studies have shown that people with obesity are more prone to allergies, and this susceptibility may be exacerbated by the use of weight gain-inducing antihistamines. This creates a potential cycle where allergy treatment could contribute to weight gain, which in turn may increase allergy susceptibility.

Why are obese individuals more likely to suffer from allergies? Several factors may contribute to this phenomenon:

• Chronic low-grade inflammation associated with obesity may enhance allergic responses
• Adipose tissue produces hormones and cytokines that can influence immune function
• Obesity can affect lung function and respiratory mechanics, potentially exacerbating allergy symptoms

Understanding this connection underscores the importance of addressing both allergy management and weight control as part of a comprehensive health strategy.

Strategies for Managing Allergies Without Weight Gain

For those concerned about the potential weight gain associated with antihistamine use, several strategies can help manage allergy symptoms while minimizing this risk:

1. Opt for loratadine (Claritin) if an antihistamine is necessary, as it’s less likely to cause weight gain
2. Consider using nasal corticosteroids as a first-line treatment for allergic rhinitis
3. Implement environmental controls to reduce allergen exposure
4. Explore immunotherapy options with an allergist for long-term allergy management
5. Maintain a healthy diet and exercise routine to counteract potential weight gain effects
6. Use antihistamines intermittently or only when absolutely necessary
7. Consult with a healthcare provider about personalized allergy management strategies

Can lifestyle changes help reduce reliance on antihistamines? Absolutely. Many allergy sufferers find that a combination of environmental controls, dietary adjustments, and natural remedies can significantly reduce their need for medication. Some effective lifestyle changes include:

• Using allergen-proof bedding covers
• Regularly cleaning and vacuuming with HEPA filters
• Maintaining low humidity levels in the home to prevent mold growth
• Incorporating anti-inflammatory foods into the diet, such as omega-3 rich fish, fruits, and vegetables
• Practicing stress-reduction techniques, as stress can exacerbate allergy symptoms

The Role of Histamine in Weight Regulation

To fully understand the impact of antihistamines on weight, it’s crucial to explore the role of histamine in the body’s weight regulation processes. Histamine is more than just an allergy mediator; it’s a neurotransmitter that plays a significant role in various physiological functions, including appetite control and metabolism.

Histamine and Appetite Suppression

How does histamine affect appetite? Research has shown that histamine has an appetite-suppressing effect. When histamine binds to receptors in the hypothalamus, it can reduce food intake and increase feelings of fullness. This effect is thought to be mediated through several mechanisms:

• Activation of histamine H1 receptors in the brain suppresses appetite
• Histamine may influence the release of other appetite-regulating hormones
• Histamine signaling can affect the reward centers in the brain associated with eating

By blocking these histamine receptors, antihistamines may inadvertently remove this natural appetite-suppressing mechanism, potentially leading to increased food intake.

Histamine and Metabolic Rate

Beyond its effects on appetite, histamine also plays a role in regulating metabolic rate. Studies have suggested that histamine can increase energy expenditure and fat oxidation. When histamine signaling is blocked by antihistamines, these metabolic benefits may be reduced, contributing to weight gain through decreased calorie burning.

What are the specific metabolic effects of histamine? Research has indicated that histamine can:

• Increase brown adipose tissue activity, enhancing calorie burning
• Promote lipolysis, the breakdown of fat for energy
• Regulate glucose metabolism and insulin sensitivity

These findings highlight the complex relationship between histamine, antihistamines, and body weight regulation, emphasizing the need for careful consideration when using these medications, especially for individuals concerned about weight management.

The Future of Allergy Treatment: Balancing Efficacy and Side Effects

As our understanding of the relationship between antihistamines and weight gain grows, researchers and pharmaceutical companies are exploring new avenues for allergy treatment that minimize unwanted side effects. The future of allergy management may involve more targeted therapies that provide relief without interfering with metabolic processes.

Emerging Allergy Treatments

What new allergy treatments are on the horizon? Several promising approaches are being investigated:

• Biologic therapies that target specific components of the allergic response
• Nanotechnology-based drug delivery systems for more targeted treatment
• Gene therapy approaches to modify the immune response to allergens
• Probiotics and microbiome-based treatments to modulate immune function

These innovative approaches aim to provide effective allergy relief while minimizing systemic side effects, including potential weight gain.

Personalized Allergy Management

The future of allergy treatment is likely to become increasingly personalized, taking into account individual factors such as genetic predisposition, environmental exposures, and co-existing health conditions. This tailored approach may help identify the most effective treatments with the lowest risk of side effects for each patient.

How might personalized allergy management look in practice? It could involve:

• Genetic testing to predict response to different allergy medications
• Advanced diagnostic techniques to pinpoint specific allergen sensitivities
• Customized immunotherapy protocols based on individual immune profiles
• Integration of wearable technology to monitor symptoms and treatment efficacy in real-time

By taking a more individualized approach to allergy management, healthcare providers may be better equipped to balance symptom relief with potential side effects, including weight gain.

The Importance of Holistic Health Management

The connection between antihistamines and weight gain underscores the importance of taking a holistic approach to health management. Allergy sufferers should work closely with healthcare providers to develop comprehensive treatment plans that address not only their allergy symptoms but also consider potential impacts on weight and overall health.

Integrating Allergy and Weight Management

For individuals struggling with both allergies and weight management, an integrated approach may be beneficial. This could involve:

• Regular consultations with both an allergist and a weight management specialist
• Developing a nutrition plan that supports both allergy management and weight control
• Incorporating exercise routines that are compatible with allergy symptoms and medications
• Exploring stress reduction techniques, as stress can exacerbate both allergies and weight gain
• Regular monitoring of both allergy symptoms and weight to adjust treatment plans as needed

By addressing these interconnected health issues simultaneously, patients may achieve better overall outcomes and quality of life.

The Role of Patient Education

Empowering patients with knowledge about the potential side effects of their medications, including weight gain, is crucial. Healthcare providers should engage in open discussions about the benefits and risks of different treatment options, allowing patients to make informed decisions about their care.

What questions should patients ask their healthcare providers about allergy treatments and weight gain? Consider the following:

• Are there alternative treatments that are less likely to cause weight gain?
• How can I monitor and manage potential weight gain while on antihistamines?
• What lifestyle modifications can help minimize the need for antihistamines?
• How often should I follow up to assess the effectiveness and side effects of my allergy treatment?

By fostering this dialogue, patients can become active participants in their healthcare decisions and work collaboratively with their providers to achieve optimal health outcomes.

In conclusion, while antihistamines remain an important tool in managing allergies, their potential impact on weight gain cannot be ignored. By understanding these effects, exploring alternative treatments, and taking a holistic approach to health management, allergy sufferers can find relief while minimizing unwanted side effects. As research continues to advance our understanding of allergies and their treatments, we can look forward to more targeted and personalized approaches that balance efficacy with overall health and well-being.

Scott D. Isaacs, MD: Endocrinologist

Allergy season is here. We are experiencing record pollen counts this year and you may be experiencing symptoms like runny nose, sneezing, and watery eyes. Many people treat seasonal allergies with over-the-counter antihistamines, but did you know that these medications could be making you gain weight? 

Studies have shown that people with obesity are more prone to allergies, and this may have to do with the medications used to treat seasonal allergies. Scientists from Yale University published a study in 2010 in the journal Obesity showing that people who took antihistamines gained weight.

Histamine is known to affect body weight. The appetite control center of the brain known as the hypothalamus contains receptors for histamine. When histamine receptors are blocked by an antihistamine medication, the brain doesn’t receive the “I’m full” signal like it normally would. The body also can’t burn calories effectively when the histamine receptor is blocked, lowering metabolism. These biological changes result in increased appetite, overeating, slower fat breakdown and weight gain. Antihistamines can also make you feel tired and unmotivated to exercise.

Antihistamines that can cause weight gain include:

• Diphenhydramine (Benadryl and others)
• Cetirizine (Zyrtec)
• Levocetirizine (Xyzal)
• Fexofenadine (Allegra)
• Hydroxyzine (Atarax, Vistaril)
• Chlorpheniramine maleate (Chlor-Trimeton)

If you need to take an antihistamine your best bet is loratadine (Claritin). This is because loratadine does not cross into the brain and therefore cannot stimulate the appetite center of the brain and does not cause fatigue.

Other side effects of antihistamines include:

• Dry mouth
• Drowsiness
• Dizziness
• Nausea and vomiting
• Restlessness or moodiness
• Trouble urinating
• Blurred vision
• Confusion

Alternative allergy treatments include steroid nasal spray and eye drops, decongestants, cromolyn sodium nasal spray and allergy shots. Frequent showers and salt-water nasal washes can also be helpful. Non-drug strategies to dealing with allergies include reducing exposure to allergy triggers like pollen, dust, mold or pet dander.  

If you’re struggling with weight loss, you need the help of an obesity medicine specialist. If you’d like to learn more about permanent weight loss, please feel free to call us or schedule an appointment with Dr. Isaacs using the online booking tool on this website.

Author

Scott Isaacs, MD
Endocrinologist and Weight Loss Specialist

Treatment of Hepatic Hypothyroidism

Hepatic hypothyroidism is not a thyroid disorder and is not treated with thyroid medications, thyroid supplements, or a thyroid diet.

March is National Nutrition Month

Today about half of all American adults have one or more chronic diseases, often related to poor diet.

February is National Heart Health Month

Heart disease doesn’t happen just to older adults. It is happening to younger adults more and more often. This is partly because the conditions that lead to heart disease are happening at younger ages.

2023 Update: Medications for Weight Loss

When people lose weight, their body begins sending signals to the brain that there is a decrease in stored energy. The brain then sends hormonal and chemical messages that increase appetite, hunger, and cravings and decrease metabolism.

January is Healthy Resolutions Month

Some people’s challenges are more daunting than others, and it can be disappointing when we abandon our resolutions after only a few weeks. No matter what you have resolved to do this year, it is always best to approach it with a plan.

Antihistamines and Weight Gain | Obesity Medicine Association

Benadryl, Allegra, Zyrtec, Claritin are all antihistamines sold throughout the United States, both over the counter and via prescription. Anyone who suffers from chronic sinus congestion, runny noses, hives, or even occasional insomnia is aware that these medications are powerful tools in our pharmaceutical arsenal. Given histamine receptors are located throughout our body, these drugs can affect us in many ways, including weight gain.

What is Histamine?

Histamine is a molecule famously known to be a key player in allergic responses. It is released by cells called mast cells at the membranes that cover our noses, mouths, lungs, and stomachs when exposed to an allergen (something that results in allergies such as pollen, dust, etc). This results in our small blood vessels known as capillaries becoming more permeable allowing white blood cells to move into the vessels to attack the foreign body. The intention of this process is to help expel potential intruders, but often our immune system overreacts and leads to burdensome runny noses, congested sinuses, and rashes.

Histamine also acts as a neurotransmitter in our brains playing a key role in wakefulness and preventing sleep, which is why Benadryl (an anti-histamine) makes you sleepy. This effect may actually be one of the reasons why anti-histamines are among the medications that can cause weight gain.

What is the relationship between antihistamines and weight gain?

The major study which somewhat demonstrates the relationship between antihistamines and weight gain come from the journal of Obesity[1] in 2010 which used the National health and Nutrition Examination Survey (NHANES) data set to study the issue. The NHANES is an annual health survey conducted by the National Center for Health Statistics (NCHS), where the NCHS staff drive trailers across the United States and conduct interviews, medical histories, physical examinations, and laboratory testing to determine the prevalence of and risk factors for major diseases. This data is then available to the public for research.

For this particular study researchers from the Yale University School of Medicine looked at the NHANES data set from 2005-2006, looking at 268 adults (174 female and 94 male) who reported the use of a prescription antihistamines such as Zyrtec and Allegra, and compared them to 599 people (401 female and 198 male) who did not, looking at differences in body mass index (BMI), cholesterol and glucose levels. After doing a statistical adjustment for gender and age, the researchers found that those who used prescription anti-histamines displayed significantly greater BMI, waist circumference, and insulin levels, but no differences between cholesterol and fasting glucose levels, demonstrating a correlation between using anti-histamines and higher weight. Specifically, anti-histamine users had an average BMI of 30 versus a BMI of 28-29 for men and women who did not use the drugs. In pounds men who used anti-histamines had an average weight of 214 pounds versus 192 and women had an average of 176 pounds versus 166 pounds.

This seems to suggest that antihistamines could be a factor in weight gain. However, the important thing to note is that this is a cross-sectional study and just because in this case antihistamine use and weight gain are related, it doesn’t mean one necessarily causes the other. Also, the study looked at only prescription antihistamines such as Zyrtec and Allegra not over-the-counter medications like Benadryl (although now many over-the-counter anti-histamines have the same strength as the prescription versions).

Still, from clinical experience and solid scientific research demonstrating how histamine affects our appetites, it is safe to say that anti-histamines probably do affect weight gain. Moreover, antipsychotics like Zyprexa have a significant anti-histamine effect and are well known to result in dramatic weight gain.

Why do anti-histamines cause weight gain?

Histamine decreases our hunger by in part affecting the appetite control center in our brains[2], and it makes sense an anti-histamine would have the opposite effect. These drugs can interfere with the “I’m full” signal coming from the rest of our bodies and lead to overeating. Medications like Allegra and Benadryl also have the effect of making us sleepier, decreasing the amount of energy we use, and leading to fewer calories burned throughout the day. While first-generation antihistamines like Benadryl are more prone to make you sleepy, even second-generation medications like Zyrtec, when broken down by the body, resulting in byproducts that have a mild sedative effect.

Do antihistamines cause weight gain?

The short answer seems to be yes. While occasionally taking a Benadryl for sleep probably won’t lead to significant weight gain, chronic use of antihistamines can interfere with weight loss efforts. If you need an antihistamine for frequent allergy symptoms, however, the best choice is Claritin because it does not cross into the brain and has less effect on appetite and sedation. Otherwise, steroid nasal sprays, decongestants, and just reducing exposures to allergens are other options.

Written by: Vivek Gupta, MD, MPH

Which drugs make you gain weight

If you are prescribed a drug and start to gain weight, the two events are not necessarily related. Some groups of drugs can really affect weight gain, but not in the way you think.

Tags:

weight loss

Excess weight

The fight against excess weight

Medications

freepik

Perhaps you are taking some kind of medication and have started noticing how the numbers on the scale are getting bigger. Look in the instructions for the group of your drug and perhaps it will be on this list.

Contents of the article

Do not self-medicate! In our articles, we collect the latest scientific data and the opinions of authoritative health experts. But remember: only a doctor can diagnose and prescribe treatment.

1. Why does the drug cause weight gain?

By itself, the drug does not form fatty tissue from nothing. Reasons your drug may cause weight gain include side effects such as:

• increased appetite

• water retention

• intense accumulation of fat from incoming food (faster than usual)

• slow metabolism 900 31

• fatigue, lethargy or weakness

2. Medicinal drugs

2.1 Antidepressants

Some antidepressants can cause weight gain by affecting the neurotransmitter serotonin, which affects our mood. You become more relaxed, your well-being improves, and with it your appetite. Other antidepressant options can cause drowsiness and fatigue, which reduces your level of activity, and therefore the expenditure of energy, which is then stored as adipose tissue.

ADVERTISING – CONTINUED BELOW

2.2 Contraceptives

This class of drugs is most often blamed for weight gain. In general, birth control pills are not associated with weight gain, especially the newer pills with lower doses of estrogen and progestin. A significant effect can be observed only with injections. And so again we return to the revision of the calorie content of the diet and the level of physical activity.

2.3 Antihistamines

Blocking histamine activity may increase appetite. Used to treat allergic conditions.

2.4 Antipsychotics and the treatment of mood disorders

Although all antipsychotics have been shown to cause some metabolic and weight changes, each drug has its own risk profile. They have a similar effect to antidepressants. This class of drugs is used for mental illness.

2.5 Beta blockers

Beta blockers are a class of heart drugs used to treat high blood pressure and chest pain (angina). They can cause fatigue. A person lacks energy and slows down, which can affect the number of calories burned per day

2.6. Corticosteroids

Steroids can affect the metabolic rate and lead to increased appetite and overeating. This class of drugs can lead to additional deposits of fat in the middle part of the body (in the abdomen). They are often used for a short time

2.7 Diabetes medicines

May cause weight gain, both through increased appetite and increased glucose uptake into cells. Too many calories in the form of glucose will lead to weight gain (as insulin injections can). But remember that nutrition and physical activity can control such effects.

2.8 Anticonvulsants, mood stabilizers and migraine medicines

Have a similar body weight gain mechanism to previous classes. Long-term use of this group of drugs can cause significant weight gain

3. What should I do?

Other drugs will not have any significant effect on your weight. Get back to the basics:

1. a balanced diet

2. regular physical activity

3. quality sleep and rest

If you are all – you are still taking one of the above drugs, consult your doctor, but do not stop the drug yourself .

(Also: How antidepressants affect weight: here’s what the scientists say)

Medicines that make you gain weight side effects. Unfortunately, doctors do not always warn about what medications can lead to, and many would like to know what to expect from a course of medications.

Tags:

The fight against excess weight

Medications

hypertension

Migraine

Getty Images

One of the most common drug side effects is weight gain. Let’s make a reservation right away – this does not happen for everyone and not always, but you can be one of those “lucky ones” who really put on weight.

We talk about drugs that can cause weight gain. We are sure that it is better to know and take some steps in advance so as not to gain weight than to accidentally discover an extra 3-5, or even 10 kg, gained over several weeks of taking the drug.

In general, it would be absolutely useful to discuss with the doctor all the possible “side effects” that the prescribed medicine can cause in order to take timely action. This, however, applies to any side effects, and not just those associated with weight. In some cases, undesirable effects are inevitable, but there are situations when their occurrence can be completely avoided or at least made less pronounced.

Steroids

Steroid preparations can be prescribed for various diseases. They make it quite easy to achieve an improvement in the condition, but the treatment is often accompanied by an undesirable effect, including insomnia, increased appetite and swelling. All this is the perfect combo for those extra pounds to literally stick in strategic places. It is important that steroids are available in different forms – these can be ointments and creams, sprays, as well as tablets. The latter just cause weight gain the most. You can reduce your chances of gaining weight by choosing the lowest possible dose for you, as well as adjusting your diet and choosing the ideal sleep pattern for you.

ADVERTISING – CONTINUED BELOW

Antidepressants

Many people say that you can gain weight on antidepressants. Fortunately, not everyone is gaining it, although this, of course, is quite real. Selective serotonin reuptake inhibitors pose the greatest danger in this regard, so if you are taking drugs whose active ingredient belongs to this class of substances, be careful.

The fact is that such drugs not only improve your mood and help you feel less depressed, but also increase your appetite. And here the connection is quite obvious: you want to eat more – you eat more – your weight increases.

If you are prone to weight gain, then discuss with your doctor in advance that you are worried about the fact that he will become more – it is likely that he will be able to choose another suitable drug for you.

Birth control pills

Oral contraceptives have many side effects, some of which are quite pleasant and desirable. But, let’s not hide, weight gain is not included in this list for everyone.

It works like this: progesterone, which is part of birth control pills, increases appetite, which causes women to eat more and gain weight. Another possible mechanism is that while taking contraceptives, the body begins to more actively retain water, and the weight also goes up because of this.

Antihistamines

Popular antihistamine-based allergy medications are most often not available by prescription. They can be prescribed by a doctor, but many people buy these drugs on their own initiative and choose the dosage on their own.

In addition to the fact that the selection of medicines still has to be done by a specialist, there is another danger. All the same kilograms that you can gain. Taking allergy medications frequently can lead to weight gain. This happens more often in women than in men. If you notice that you are really gaining weight on the background of a course of antihistamines, but at least try to change the dosage form: the spray in this case will be much less dangerous than tablets.

Blood pressure medications

Medicines prescribed for hypertension, such as beta-blockers and angiotensin receptor blockers, also affect weight.