Calma (Dimenhydrinate)
Medicated chewing gum for prevention and treatment of motion sickness
Quick Facts About Calma
Key Takeaways About Calma
- Prevents and treats motion sickness: Calma is specifically designed as a medicated chewing gum that delivers dimenhydrinate through the lining of the mouth for rapid absorption
- Take before travel: Chew one gum for at least 10 minutes, ideally 15–30 minutes before you expect to feel motion sick, for best results
- May cause drowsiness: Dimenhydrinate is a sedating antihistamine — avoid driving or operating machinery until you know how it affects you
- Not for children under 12: Calma is only approved for adults and children aged 12 years and older due to insufficient safety data in younger children
- Maximum 4 gums per day: Do not exceed the recommended daily dose; if nausea persists, additional gums can be taken at 30-minute intervals up to the maximum
What Is Calma and What Is It Used For?
Calma is a medicated chewing gum containing 20 mg of dimenhydrinate, a first-generation antihistamine that prevents and relieves nausea and vomiting caused by motion sickness. It works by blocking histamine receptors and muscarinic receptors in the brain's vomiting center and vestibular system.
Calma belongs to a class of medications known as first-generation H1 antihistamines. Its active ingredient, dimenhydrinate, is actually a combination of two compounds: diphenhydramine (a potent antihistamine) and 8-chlorotheophylline (a mild stimulant related to caffeine). This combination was designed to provide the anti-nausea effects of diphenhydramine while partially offsetting its sedative properties.
The medication is specifically formulated as a medicated chewing gum, which offers several advantages over traditional tablet forms of dimenhydrinate. When you chew the gum, the active ingredient is released gradually and absorbed through the buccal mucosa (the lining of your mouth). This route of absorption allows for a more rapid onset of action compared to swallowing a tablet, as the drug bypasses the initial liver metabolism that occurs with oral ingestion.
Motion sickness — also known as travel sickness or kinetosis — occurs when there is a conflict between the sensory signals your brain receives from your eyes, inner ears, and body. For example, when you are reading in a moving car, your eyes tell your brain you are stationary, while your inner ears detect motion. This mismatch triggers the release of histamine and acetylcholine in the vomiting center of the brainstem, leading to nausea and vomiting.
Dimenhydrinate works by blocking both histamine H1 receptors and muscarinic acetylcholine receptors in the vestibular system and the chemoreceptor trigger zone. By reducing these chemical signals, it suppresses the sensation of nausea and the urge to vomit. The World Health Organization (WHO) includes dimenhydrinate on its Model List of Essential Medicines as a treatment for nausea and vomiting, underscoring its importance in global healthcare.
How does the chewing gum formulation work?
The medicated chewing gum is designed to release dimenhydrinate during the chewing process. The gum base contains a special polymer matrix that releases the active ingredient when mechanically worked by chewing. For optimal effect, you should chew the gum steadily for at least 10 minutes. During this time, dimenhydrinate dissolves in your saliva and is absorbed through the mucous membranes of your mouth, entering your bloodstream directly. This buccal absorption provides a faster onset of action — typically within 15 to 30 minutes — compared to conventional tablets that must first dissolve in the stomach.
It is important not to swallow the chewing gum. The gum base itself is not designed to be digested and offers no therapeutic benefit if swallowed. The effect of each gum lasts approximately 3 to 6 hours, providing convenient coverage for most journeys.
What conditions does Calma treat?
Calma is indicated for the prevention and treatment of motion sickness associated with various forms of travel. It is effective against nausea and vomiting caused by:
- Car sickness — the most common form of motion sickness, particularly in passengers
- Sea sickness — caused by the rolling and pitching motion of boats and ships
- Air sickness — triggered by turbulence and changes in altitude during flights
- Bus and train sickness — associated with irregular movements during land travel
While Calma is primarily marketed for motion sickness, your doctor may prescribe dimenhydrinate in other formulations for additional conditions such as vertigo-associated nausea, post-operative nausea, or nausea related to inner ear disorders. Always follow your healthcare provider's specific instructions if Calma has been prescribed for a use not listed in the product information.
What Should You Know Before Taking Calma?
Before taking Calma, it is essential to be aware of contraindications including acute asthma, porphyria, narrow-angle glaucoma, and severe prostatic hypertrophy. Calma contains aspartam (a source of phenylalanine) and should not be used by people with phenylketonuria. Consult your doctor if you have chronic lung disease, epilepsy, or cardiovascular disease.
Like all medications, Calma is not suitable for everyone. Understanding the contraindications, warnings, and precautions will help you use this medicine safely. The information below summarizes the key safety considerations based on the approved product information and international clinical guidelines.
Contraindications
You must not take Calma if any of the following apply to you:
- Allergy to dimenhydrinate or any of the other ingredients in the chewing gum (see the ingredients section below)
- Acute asthma attacks — dimenhydrinate may thicken bronchial secretions and worsen respiratory distress
- Porphyria — a group of rare inherited enzyme disorders that affect the production of heme, a component of hemoglobin
- Narrow-angle glaucoma — the anticholinergic effects of dimenhydrinate can increase intraocular pressure, potentially worsening this condition
- Severe prostatic hypertrophy or severe urethral stricture — the anticholinergic properties may cause urinary retention
- Phenylketonuria (PKU) — Calma contains aspartam, which is a source of phenylalanine. Patients with PKU cannot properly metabolize phenylalanine, and its accumulation can cause serious neurological damage
Calma contains 3 mg of aspartam per chewing gum. Aspartam is a source of phenylalanine. If you have been diagnosed with phenylketonuria (PKU), a rare inherited metabolic disorder, you must not take Calma. Phenylalanine accumulation can cause severe neurological harm.
Warnings and Precautions
Talk to your doctor, pharmacist, or nurse before taking Calma if you have any of the following conditions:
- Chronic lung disease or asthma — dimenhydrinate has anticholinergic effects that may thicken bronchial secretions and impair mucociliary clearance
- Prostatic hypertrophy (non-severe) — even moderate enlargement of the prostate can be affected by anticholinergic drugs, potentially causing difficulty urinating
- Urethral stricture — narrowing of the urethra combined with anticholinergic effects may lead to urinary retention
- Pyloric stenosis — narrowing at the stomach outlet may be worsened by the reduction in gastrointestinal motility caused by anticholinergic agents
- Seizure disorders (epilepsy, eclampsia) — dimenhydrinate can lower the seizure threshold in susceptible individuals
- Cardiovascular disease — anticholinergic effects may cause tachycardia (rapid heart rate) and should be used cautiously in patients with heart conditions
- Impaired kidney function — reduced renal clearance may lead to drug accumulation and increased side effects
- Severe liver disease — as dimenhydrinate is primarily metabolized in the liver, impaired hepatic function may prolong and intensify its effects
- Acute porphyria — the drug may trigger an acute porphyric episode
- Alcohol dependence — the sedative effects of dimenhydrinate and alcohol are additive, creating a risk of excessive central nervous system depression
- Pheochromocytoma — a rare adrenal gland tumor; antihistamines may interfere with diagnostic testing and catecholamine regulation
Pregnancy and Breastfeeding
If you are pregnant, breastfeeding, think you may be pregnant, or are planning to have a baby, consult your doctor or pharmacist before taking Calma. The available evidence and international guidelines provide the following guidance:
Pregnancy: Calma should only be used during pregnancy after careful consideration and under the advice of a healthcare provider. While large observational studies have not demonstrated a clear teratogenic risk with dimenhydrinate, the drug must not be used during the last weeks of pregnancy. Dimenhydrinate has been shown to potentially stimulate uterine contractions, which could pose a risk to the pregnancy. The European Medicines Agency (EMA) and the British National Formulary (BNF) both recommend caution with first-generation antihistamines during pregnancy.
Breastfeeding: Dimenhydrinate passes into breast milk. However, at normal doses and with occasional use, it is unlikely to affect the nursing infant in significant amounts. If you need to use Calma more than occasionally while breastfeeding, consult your doctor. Prolonged or frequent use may lead to drowsiness or irritability in the breastfed infant. The American Academy of Pediatrics classifies diphenhydramine (a component of dimenhydrinate) as usually compatible with breastfeeding when used occasionally.
Driving and Operating Machinery
Calma can impair your ability to drive and operate machinery. As a first-generation antihistamine, dimenhydrinate readily crosses the blood-brain barrier and can cause significant drowsiness, reduced alertness, and slower reaction times. These effects are well documented in the medical literature and can persist for several hours after taking the medication.
You should not drive, operate heavy machinery, or perform activities requiring sharp mental alertness until you know how Calma affects you personally. The sedative effect varies between individuals — some people experience marked drowsiness, while others notice minimal impairment. If you are taking Calma for the first time, it is advisable to test your response before undertaking any activity that requires full alertness.
Calma can significantly impair your reaction time and concentration. Do not drive or operate machinery until you are certain this medicine does not affect your ability to do so safely. The combination of Calma with alcohol, sedatives, or sleeping tablets increases the risk of impairment.
Important Information About Calma's Excipients
Calma contains several inactive ingredients that may be relevant for certain patients:
- Aspartam (3 mg per gum) — a phenylalanine source; contraindicated in phenylketonuria (PKU)
- Lactose (<1 mg) — present in very small amounts, unlikely to cause problems for most lactose-intolerant individuals
- Glucose (10 mg) — should be considered by patients with glucose intolerance
- Sucrose (406 mg per gum) — relevant for patients with rare hereditary sugar intolerances and those managing diabetes
- Sorbitol (285 mg per gum) — a source of fructose; patients with hereditary fructose intolerance should not use Calma
- Sodium (<1 mmol / 23 mg per gum) — essentially sodium-free
How Does Calma Interact with Other Drugs?
Calma (dimenhydrinate) has clinically significant interactions with sedatives, anxiolytics, sleeping pills, alcohol, MAO inhibitors, certain anti-Parkinson medications, beta-blockers, and anticholinergic drugs. The most important interaction is the additive sedation with CNS depressants, which can lead to excessive drowsiness and impaired function.
Drug interactions occur when one medication affects how another medication works, potentially increasing side effects or reducing effectiveness. Because dimenhydrinate has both antihistaminic and anticholinergic properties, it can interact with a wide range of medications. The following table summarizes the most important drug interactions to be aware of when taking Calma.
| Interacting Drug/Substance | Type of Interaction | Clinical Effect | Recommendation |
|---|---|---|---|
| Alcohol | Additive CNS depression | Increased drowsiness, impaired coordination, risk of respiratory depression | Avoid alcohol while taking Calma |
| Sedatives & Anxiolytics (benzodiazepines, etc.) | Additive CNS depression | Enhanced sedation, excessive drowsiness | Avoid concurrent use or use with caution under medical supervision |
| Sleeping pills (hypnotics) | Additive CNS depression | Profound sedation, risk of oversedation | Avoid concurrent use |
| MAO inhibitors | Increased anticholinergic effects | Intensified side effects (dry mouth, urinary retention, constipation, tachycardia) | Avoid — consult your doctor |
| Beta-blockers | Pharmacokinetic interaction | May alter the metabolism or effects of either drug | Use with caution — inform your doctor |
| Anticholinergic drugs (atropine, ipratropium) | Additive anticholinergic effects | Increased risk of dry mouth, blurred vision, urinary retention, constipation, confusion | Use with caution — monitor for anticholinergic toxicity |
| Anti-Parkinson drugs | Additive anticholinergic effects | Enhanced anticholinergic side effects | Use with caution — consult your doctor |
| Tricyclic antidepressants | Additive anticholinergic & sedative effects | Increased drowsiness, dry mouth, urinary retention | Use with caution — inform your doctor |
| Ototoxic drugs (aminoglycosides) | Masking of symptoms | Dimenhydrinate may mask early signs of ototoxicity (dizziness, tinnitus) | Use with caution — monitor hearing |
Major Interactions
The most clinically significant interactions involve substances that depress the central nervous system (CNS). Alcohol, sedatives, anxiolytics (such as benzodiazepines), and sleeping pills should not be used concurrently with Calma. The combined sedative effect can lead to excessive drowsiness, impaired cognitive function, dangerous levels of sedation, and in extreme cases, respiratory depression. Research published in the Journal of Clinical Pharmacology has demonstrated that the combination of first-generation antihistamines with alcohol impairs driving ability to a degree comparable to being legally intoxicated.
MAO inhibitors (monoamine oxidase inhibitors), a class of antidepressants, represent another major interaction. MAO inhibitors can intensify and prolong the anticholinergic effects of dimenhydrinate, potentially leading to dangerous side effects including hypertensive crisis, severe dry mouth, urinary retention, and confusion. If you are taking an MAO inhibitor, you should not use Calma without explicit approval from your prescribing physician.
Minor Interactions
Beta-blockers may interact with dimenhydrinate through pharmacokinetic mechanisms, though the clinical significance is generally modest. Anticholinergic drugs, including atropine-containing eye drops and ipratropium bromide (a bronchodilator), can produce additive anticholinergic effects when combined with Calma. While these interactions are less dangerous than those with CNS depressants, they can cause uncomfortable symptoms such as dry mouth, blurred vision, constipation, and difficulty urinating, particularly in older adults.
It is worth noting that dimenhydrinate may mask the symptoms of ototoxicity (damage to the inner ear) caused by other medications, such as aminoglycoside antibiotics. If you are taking any medication that is known to affect hearing, tell your doctor before using Calma.
Before taking Calma, inform your healthcare provider about all medications you are currently taking, have recently taken, or plan to take. This includes prescription medicines, over-the-counter drugs, herbal supplements, and vitamins. Drug interactions can sometimes be unpredictable, and your healthcare provider can help you assess whether it is safe to take Calma alongside your other medications.
What Is the Correct Dosage of Calma?
The recommended dose for adults and children over 12 years is one chewing gum (20 mg dimenhydrinate) chewed for at least 10 minutes, taken 15–30 minutes before travel. If nausea persists, a second gum can be taken after 30 minutes. Maximum daily dose is 4 gums (80 mg). Not recommended for children under 12.
Always take Calma exactly as described in the product information or as directed by your doctor, pharmacist, or nurse. The following dosage guidelines are based on the approved product information and established clinical practice.
Adults and Children Over 12 Years
Standard Dosing
- Prevention: Chew one gum (20 mg) for at least 10 minutes, starting 15–30 minutes before travel
- Treatment: If nausea develops despite the first dose, chew an additional gum after 30 minutes
- Repeat dosing: This can be repeated once more if needed (third gum), again after a 30-minute interval
- Duration of effect: Each gum provides relief for approximately 3–6 hours
- Maximum daily dose: 4 chewing gums (80 mg dimenhydrinate) in 24 hours
The chewing gum must be chewed steadily and continuously for at least 10 minutes to ensure proper release and absorption of the active ingredient. Do not swallow the gum — it is designed to deliver the medication through the lining of your mouth. After chewing, dispose of the gum responsibly.
For optimal prevention, timing is important. Taking Calma 15 to 30 minutes before the anticipated onset of motion sickness allows the drug to reach therapeutic levels in the bloodstream before the triggering stimulus begins. However, if you forgot to take it preventively, Calma can also be taken after symptoms have started, though the response may be slightly delayed.
Children
Pediatric Information
Calma is not recommended for children under 12 years of age due to insufficient data regarding safety and efficacy in this age group. The European Medicines Agency (EMA) guidelines require adequate clinical trial data before a medication can be recommended for pediatric use, and such data are not available for this specific formulation.
For motion sickness in younger children, consult your pediatrician or pharmacist for age-appropriate alternatives. Non-pharmacological approaches — such as looking at the horizon, sitting in the front seat, and ensuring good ventilation — should be tried first for children.
Elderly Patients
While no specific dose adjustment is explicitly stated in the product information, older adults should use Calma with particular caution. First-generation antihistamines such as dimenhydrinate are included on the Beers Criteria list of potentially inappropriate medications for older adults, published by the American Geriatrics Society. This is because elderly patients are more susceptible to the anticholinergic side effects (confusion, urinary retention, constipation, dry mouth) and the sedative effects (increased fall risk, cognitive impairment) of these drugs.
If you are over 65, discuss with your doctor whether Calma is appropriate for you. Lower doses or alternative medications with fewer anticholinergic effects may be recommended.
Missed Dose
Since Calma is used on an as-needed basis (when travel is anticipated or motion sickness symptoms occur), there is no regular dosing schedule to miss. If you forgot to take Calma before travel and have already developed motion sickness, you can still take it — the gum will help relieve existing symptoms, though it works best when taken preventively.
Overdose
If you take too much Calma, or if a child accidentally ingests the medicine, contact your local poison control center or emergency services immediately for risk assessment and guidance.
Symptoms of dimenhydrinate overdose may include severe drowsiness, confusion, dilated pupils (mydriasis), dry mouth, flushing, tachycardia (rapid heart rate), and gastrointestinal symptoms. In severe cases, particularly in children, overdose can lead to hallucinations, seizures, and respiratory depression. Seek immediate medical attention if overdose is suspected.
| Patient Group | Dose | Timing | Maximum Daily Dose |
|---|---|---|---|
| Adults (18+) | 1 gum (20 mg), chew for ≥10 min | 15–30 min before travel; repeat after 30 min if needed | 4 gums (80 mg) |
| Children 12–17 years | 1 gum (20 mg), chew for ≥10 min | 15–30 min before travel; repeat after 30 min if needed | 4 gums (80 mg) |
| Children under 12 | Not recommended | N/A | N/A |
| Elderly (65+) | 1 gum (20 mg) — use with caution | 15–30 min before travel | Consult doctor; consider lower maximum |
What Are the Side Effects of Calma?
The most commonly reported side effects of Calma include drowsiness, dizziness, headache, dry mouth, and temporary numbness in the mouth (from the local anesthetic effect of the active ingredient). Most side effects are mild and transient. Serious side effects are rare but can include allergic skin reactions and photosensitivity.
Like all medicines, Calma can cause side effects, although not everybody gets them. The side effects of dimenhydrinate are primarily related to its antihistaminic and anticholinergic properties. Most side effects are dose-dependent and transient, meaning they are more likely to occur at higher doses and typically resolve once the medication is discontinued.
A characteristic side effect unique to the chewing gum formulation is a temporary numbness or tingling sensation in the mouth. This is harmless and results from the local anesthetic properties of dimenhydrinate itself. The sensation typically resolves within minutes after you stop chewing.
The following frequency categories are used to classify side effects according to international pharmacovigilance standards. For Calma, most side effects are reported with unknown frequency because they are derived from post-marketing surveillance and spontaneous reporting rather than controlled clinical trials:
Commonly Reported
- Drowsiness / sedation — the most frequent side effect, related to H1 receptor blockade in the brain
- Dizziness — can occur due to central nervous system depression
- Headache — may occur during or after use
- Dry mouth — caused by anticholinergic (antimuscarinic) action
- Temporary oral numbness — a local effect unique to the gum formulation, harmless and short-lived
Less Commonly Reported
- Coordination problems — impaired motor coordination due to CNS effects
- Tremor — involuntary shaking, usually mild
- Visual disturbances — including blurred vision from anticholinergic pupil dilation
- Dry nasal mucosa — drying of the nasal passages
- Nausea, vomiting, abdominal pain — paradoxically, the very symptoms the drug treats can occur as side effects
- Constipation or diarrhea — gastrointestinal disturbance
Rarely Reported
- Allergic skin reactions — rash, itching, or hives
- Photosensitivity — increased sensitivity of the skin to sunlight, potentially causing sunburn more easily
- Difficulty urinating — urinary retention from anticholinergic effects, more common in elderly men with prostatic hypertrophy
When to seek medical attention for side effects
Most side effects of Calma are mild and resolve on their own. However, you should seek medical attention if you experience:
- Signs of an allergic reaction such as skin rash, swelling of the face or throat, or difficulty breathing
- Severe confusion or hallucinations (more likely with overdose or in elderly patients)
- Inability to urinate despite feeling the urge
- Rapid or irregular heartbeat
- Severe or persistent side effects that concern you
It is important to report suspected side effects after a medicine has been authorized. This allows continuous monitoring of the medicine's benefit-risk balance. Healthcare professionals and patients can report suspected side effects to their national pharmacovigilance authority (e.g., the FDA MedWatch program in the United States, the MHRA Yellow Card Scheme in the United Kingdom, or the EMA EudraVigilance system in the European Union).
How Should You Store Calma?
Store Calma at room temperature below 25°C (77°F), away from direct sunlight and moisture. Keep out of the sight and reach of children. Do not use after the expiry date printed on the packaging. Do not dispose of medicines in wastewater or household waste.
Proper storage of medications is essential to ensure they remain safe and effective throughout their shelf life. Calma should be stored according to the following guidelines:
- Temperature: Store at or below 25°C (77°F). Do not freeze. Avoid storing in hot environments such as a car dashboard in summer or near radiators.
- Light and moisture: Keep the gum in its original blister packaging until ready to use. The blister pack protects the medicated gum from moisture and light, which could degrade the active ingredient.
- Child safety: Keep this medicine out of the sight and reach of children. The chewing gum formulation may be particularly attractive to children, who might mistake it for regular chewing gum.
- Expiry date: Do not use Calma after the expiry date stated on the carton and blister pack. The expiry date refers to the last day of that month.
For responsible disposal, do not throw unused medicines in wastewater or household waste. Ask your pharmacist how to dispose of medicines you no longer need. These measures help protect the environment by preventing pharmaceutical contamination of water systems.
When traveling, keep Calma in its original packaging and within easy reach. If you are traveling to a hot climate, consider storing the gum in an insulated bag to maintain temperatures below 25°C. The medicated gum is available in packs of 2, 10, and 20 pieces, making the smaller travel-size packs convenient for journeys.
What Does Calma Contain?
Each Calma medicated chewing gum contains 20 mg of the active ingredient dimenhydrinate. Inactive ingredients include aspartam, calcium carbonate, gum base, sorbitol, sucrose (406 mg), menthol, and peppermint flavoring. The gum is white, round, and biconvex in shape.
Active Ingredient
The active pharmaceutical ingredient is dimenhydrinate 20 mg per chewing gum. Dimenhydrinate is a 1:1 salt of diphenhydramine and 8-chlorotheophylline. Diphenhydramine provides the primary antihistaminic and anti-emetic action, while 8-chlorotheophylline (a xanthine derivative related to caffeine and theophylline) provides mild stimulant properties that partially counteract diphenhydramine's sedative effect.
Inactive Ingredients (Excipients)
The other ingredients in Calma medicated chewing gum are:
- Aspartam
- Calcium carbonate
- Dextrin
- Dimethylaminoethyl methacrylate methyl (butyl) methacrylate copolymer
- Gum base
- Hard fat
- Liquid glucose
- Macrogol (polyethylene glycol)
- Light magnesium oxide
- Magnesium stearate
- Menthol
- Methacrylic acid methyl methacrylate copolymer
- Montan glycol wax
- Peppermint flavor (contains lactose)
- Potassium dihydrogen phosphate
- Povidone
- Saccharin sodium
- Sorbitol
- Colloidal anhydrous silicon dioxide
- Sucrose
- Talc
- Titanium dioxide (E171)
- White beeswax
Each chewing gum contains 406 mg of sugar (sucrose). This is relevant for individuals monitoring their sugar intake, such as those with diabetes. The gum also contains 285 mg of sorbitol, which is a source of fructose. Patients with hereditary fructose intolerance should not use this product.
Physical Description
Calma medicated chewing gum is white, round, and biconvex (curved on both sides) with a sugar coating. It is available in pack sizes of 2, 10, and 20 chewing gums, packaged in aluminum blister packs within a cardboard carton.
Manufacturer Information
The marketing authorization holder is Cooper Consumer Health B.V., Verrijn Stuartweg 60, 1112AX Diemen, Netherlands. The manufacturer is Hermes Pharma Ges.m.b.H., Schwimmschulweg 1a, 9400 Wolfsberg, Austria.
Frequently Asked Questions About Calma
Calma is a medicated chewing gum containing 20 mg dimenhydrinate, used to prevent and treat motion sickness (travel sickness). It is effective against nausea and vomiting caused by car, bus, boat, and air travel. The gum is chewed for at least 10 minutes, ideally 15–30 minutes before the journey begins, and provides relief for 3–6 hours.
Calma is not recommended for children under 12 years of age due to insufficient safety and efficacy data. For children aged 12 and over, the dosage is the same as for adults: one chewing gum chewed for at least 10 minutes, with a maximum of 4 gums per day. Parents should consult a healthcare provider for motion sickness options for younger children.
Yes, drowsiness is one of the most commonly reported side effects of Calma. Dimenhydrinate is a first-generation antihistamine that crosses the blood-brain barrier, which can cause sedation. You should not drive or operate machinery until you know how Calma affects you. The sedative effect can be intensified by alcohol, sleeping pills, and anti-anxiety medications.
Calma should only be used during pregnancy after careful consideration and consultation with a healthcare provider. It must not be used during the last weeks of pregnancy, as dimenhydrinate may stimulate uterine contractions. While dimenhydrinate passes into breast milk, it is unlikely to affect nursing infants at occasional use. Consult your doctor for frequent use during breastfeeding.
Calma begins working within 15–30 minutes when chewed properly. The active ingredient dimenhydrinate is absorbed through the lining of the mouth (buccal mucosa) during chewing. For best results, start chewing one gum 15–30 minutes before you expect to feel motion sick. The effect lasts 3–6 hours. If nausea still occurs, you can take another gum after 30 minutes.
If you take too much Calma (more than 4 gums in a day) or if a child accidentally ingests the medicine, contact your local poison control center or emergency services immediately for risk assessment and advice. Symptoms of overdose may include severe drowsiness, confusion, dilated pupils, dry mouth, flushing, and in severe cases, seizures or hallucinations.
References
- World Health Organization. WHO Model List of Essential Medicines – 23rd List. Geneva: WHO; 2023. Dimenhydrinate listed as an antiemetic for motion sickness.
- European Medicines Agency. Summary of Product Characteristics (SmPC) Guidelines for Antihistamines. EMA/CHMP/ICH/135/1995. Amsterdam: EMA; 2023.
- British National Formulary (BNF). Dimenhydrinate. In: BNF 86. London: BMJ Group and Pharmaceutical Press; 2024.
- Golding JF. Motion sickness. Handbook of Clinical Neurology. 2016;137:371–390. doi:10.1016/B978-0-444-63437-5.00027-3
- Murdin L, Golding J, Bronstein A. Managing motion sickness. BMJ. 2011;343:d7430. doi:10.1136/bmj.d7430
- Weinstein SE, Stern RM. Comparison of marezine and dramamine in preventing symptoms of motion sickness. Aviation, Space, and Environmental Medicine. 1997;68(10):890–894.
- American Geriatrics Society 2023 Updated AGS Beers Criteria for Potentially Inappropriate Medication Use in Older Adults. Journal of the American Geriatrics Society. 2023;71(7):2052–2081.
- Shupak A, Gordon CR. Motion sickness: advances in pathogenesis, prediction, prevention, and treatment. Aviation, Space, and Environmental Medicine. 2006;77(12):1213–1223.
- FDA Drug Safety Communication. First-generation antihistamines: Drug safety and risk assessment. Silver Spring, MD: U.S. Food and Drug Administration; 2023.
- Cooper Consumer Health B.V. Calma 20 mg Medicated Chewing Gum – Product Information Leaflet. Diemen, Netherlands; updated October 2025.
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