What is Buclizine?
Buclizine is a first-generation antihistamine belonging to the piperazine derivative family of drugs [1.4.1, 1.7.4]. Initially approved by the FDA in 1957, its primary uses are for the prevention and treatment of nausea, vomiting, and dizziness associated with motion sickness and vertigo [1.4.1]. Like other sedating antihistamines, it works by blocking histamine H1 receptors in the brain [1.3.2]. It also possesses anticholinergic properties, which contribute to its antiemetic (anti-vomiting) effects by suppressing nerve pathways from the inner ear's vestibular apparatus to the part of the brain that controls vomiting [1.3.3, 1.3.5].
Beyond its primary indications, buclizine has been studied for treating migraine attacks and has been used in some countries for allergic conditions [1.4.4]. More recently, it has been reintroduced and marketed, particularly in regions like India, as an appetite stimulant to promote weight gain, especially in children [1.7.1, 1.3.1]. However, this use is controversial and not universally validated, with many experts calling for more robust clinical trials to confirm its efficacy and safety for this purpose [1.4.2, 1.2.1].
The Link Between Buclizine and Weight Gain
Weight gain is a recognized side effect of buclizine [1.2.6]. The drug is often included in multivitamin formulations specifically marketed as appetite enhancers to promote weight gain [1.2.4, 1.2.5]. While the connection is acknowledged, the precise pharmacological mechanism behind buclizine's effect on appetite and weight is not well understood [1.3.1].
Several theories exist:
- Hypoglycemic Action: One postulation is that buclizine causes a mild drop in blood sugar (hypoglycemia), which in turn may stimulate feelings of hunger [1.2.2].
- Central Nervous System Effects: Its action on acetylcholine receptors in the central nervous system could also play a role in affecting hunger signals [1.2.2].
- Histamine Blockade: Research has shown that blocking histamine receptors can stimulate appetite. Classical antihistamines like cyproheptadine and promethazine have demonstrated significant increases in food intake [1.7.3]. Buclizine, as a potent H1 receptor antagonist, likely shares this effect [1.3.2].
Despite being marketed for this purpose, the evidence supporting its use as a dedicated appetite stimulant is based on older, small-scale studies with questionable methodology [1.3.4]. The medical community remains divided, with some practitioners warning against its use for weight gain, especially in children, due to the lack of strong evidence and potential for side effects [1.2.8].
Buclizine Compared to Other Appetite-Stimulating Antihistamines
Buclizine is not the only antihistamine associated with weight gain. Cyproheptadine is another well-known first-generation antihistamine used off-label to stimulate appetite [1.7.7]. The table below compares these two medications.
| Feature | Buclizine | Cyproheptadine |
|---|---|---|
| Primary Use | Prevention of nausea, vomiting, motion sickness, vertigo [1.4.1] | Treatment of allergic reactions, such as hay fever and skin hives [1.7.7] |
| Mechanism | H1 receptor antagonist with anticholinergic effects [1.3.2] | H1 receptor antagonist with antiserotonergic effects |
| Appetite Stimulation | Used as an appetite stimulant, though evidence is considered insufficient by many experts [1.2.1, 1.2.4] | Commonly used off-label as an appetite stimulant [1.7.7] |
| Common Side Effects | Drowsiness, dry mouth, headache, dizziness, potential weight gain [1.5.4, 1.5.5] | Drowsiness, dizziness, increased appetite, weight gain |
| Status | Available, but its use as an appetite stimulant is controversial [1.4.2] | Prescription only; its counterpart was banned in some regions due to adverse effects [1.7.2, 1.7.7] |
Managing Potential Weight Gain
If you are prescribed a medication like buclizine and are concerned about potential weight gain, it is crucial to speak with your healthcare provider before making any changes [1.6.3]. They can help you weigh the benefits of the medication against its side effects.
Strategies to manage medication-related weight gain include:
- Dietary Adjustments: Focus on a balanced diet with portion control. Increasing fiber and protein can help you feel full for longer [1.6.6]. Keeping a food diary can increase awareness of eating habits [1.6.3].
- Regular Physical Activity: Incorporating regular exercise helps burn calories and can offset weight gain. It also offers mental health benefits [1.6.2]. Activities could include walking, swimming, or cycling [1.6.1].
- Lifestyle Changes: Limiting sugary drinks, avoiding eating in front of the TV, ensuring adequate sleep, and managing stress are all important components of weight management [1.6.1, 1.6.6].
- Medical Consultation: Your doctor might suggest switching to an alternative medication with a lower risk of weight gain, adjusting the dosage, or, in some cases, prescribing another medication like metformin to counteract the weight gain [1.6.2, 1.6.4]. Never stop or alter your medication dosage without professional medical advice [1.6.5].
Conclusion
So, does buclizine make you gain weight? Yes, it can. Weight gain is a listed side effect, and the drug is actively marketed as an appetite stimulant, often in combination with vitamins [1.2.4, 1.2.6]. This effect is believed to stem from its antihistaminic and central nervous system actions, though the exact mechanism remains unclear [1.2.2, 1.3.1]. However, the use of buclizine solely for weight gain is a point of contention in the medical community due to a lack of robust, modern clinical evidence [1.2.1]. Patients should be aware of this potential side effect and discuss any concerns, along with management strategies, with their healthcare provider.
For more information on managing medication-induced weight gain, a helpful resource is the Obesity Action Coalition. [https://www.obesityaction.org/resources/prescription-medications-weight-gain/]
