Carsickness in Dogs – Motion + Anxiety
Most dogs that “get carsick” actually have two distinct problems that often coexist:
- Motion sickness – drooling, vomiting, lip-licking, restlessness
- Anxiety – panting, shaking, whining, hiding, trying to escape
Treatment differs for each component.
Medication Comparison
Motion Sickness (Primary)
CERENIA (maropitant) — GOLD STANDARD
- 8 mg/kg PO q24h starting 2 hours before travel
- NK1 receptor antagonist – blocks nausea signal at brainstem
- No sedation
- Specifically labelled for canine motion sickness
- Safe for up to 4 consecutive days
Anxiety (Primary)
TRAZODONE — first-line
- 3-7 mg/kg PO q8-24h PRN, 1-2 hours before travel
- SARI antidepressant with rapid anxiolytic effect
- Mild sedation expected
- Safer than acepromazine
GABAPENTIN — excellent adjunct
- 10-25 mg/kg PO q8-12h PRN, 2 hours before travel
- Anxiolytic + mild sedation
- Safe with most meds; can combine with trazodone for severe cases
- Side effect: mild ataxia
SILEO (dexmedetomidine oromucosal gel)
- 125 mcg/m² body surface area applied to gum 30 min before
- Specifically labelled for noise aversion + anxiety
- Rapid onset; less sedation than oral alpha-2 agonists
Falling Out of Favor
ACEPROMAZINE – older drug
- Sedates WITHOUT true anxiolytic effect – dog still anxious but unable to express
- Can sensitize to noise/anxiety
- AVOID in MDR1 breeds (Collie, Aussie, Sheltie, Border Collie, GSD, Old English)
- AVOID in brachycephalic dogs
- Better modern alternatives available
Adjuncts (OTC)
ADAPTIL (DAP pheromone)
- Synthetic dog appeasing pheromone
- Spray on bandana or in car 15-30 min before travel
- Adaptil collar provides 4-week continuous release
- Gentle effect; good alongside medications
DIPHENHYDRAMINE (Benadryl)
- 2-4 mg/kg PO q8-12h
- Mild anti-nausea + sedative
- Avoid formulations with decongestants or acetaminophen
Recommended Protocols
Motion Sickness Predominant
Cerenia + behavioral training. Most dogs do beautifully.
Anxiety Predominant
Trazodone + Adaptil + behavioral desensitization.
Both / Severe
Combination: Cerenia + Trazodone + Gabapentin + Adaptil + behavioral.
Behavioral Desensitization – 5-Step Protocol
For long-term success, combine medications with desensitization – reduces or eliminates medication need over time.
Step 1: Positive Car Associations (1-2 weeks)
- Feed meals in stationary car
- Treats and games in stationary car
- Just sit in car together with engine off
- NO driving yet
Step 2: Engine On, No Movement (3-7 days)
- Sit in car with engine running
- Treats and praise
- Still no driving
Step 3: Driveway and Short Distances (1-2 weeks)
- Drive to end of driveway, treat, drive back
- Gradually expand to round-the-block trips
- End at HOME (not always at vet/groomer/dog park — destination matters)
Step 4: Positive Destinations (2-4 weeks)
- Drive to favorite places (park, friend’s house, treat shop, beach)
- Short trips with positive endings
- Build “car = good places” association
Step 5: Longer Trips With Breaks (ongoing)
- Gradually extend duration
- Frequent breaks for water, stretching, sniffing
- Calm crate or harness in car
Travel Day Tips
- Empty stomach 4-6 hours before (light meal or fast); puppies need shorter fast (hypoglycemia)
- Exercise before – tired dog calmer; 30-60 min walk/play; bladder/bowel empty
- CRASH-TESTED HARNESS (Sleepypod, Kurgo) or secured crate – unrestrained dog is dangerous
- Cool temperature 18-21°C; brachys especially sensitive
- Facing forward – visual stabilization helps motion sickness
- Fresh air – crack window or A/C circulation
- Smooth driving – predictable acceleration/braking; avoid sudden turns
- Frequent breaks every 1-2 hours
- Familiar items – blanket from home, favorite toy
- Quiet environment – some dogs prefer classical music
Critical Safety
- NEVER LEAVE DOG ALONE IN PARKED CAR – even cool day, even briefly. Cars heat 10-20°C above outside in minutes; dogs die of heat stroke quickly. Brachys especially vulnerable.
- RESTRAINT IS CRITICAL – unrestrained dog at 30 mph = ~60 kg of projectile force in collision. Use crash-tested harness or secured crate.
- TRIAL DOSE AT HOME before relying on it for actual travel day – individual responses vary.
Puppy Carsickness
Often improves with vestibular system maturation by 12 months. Continue gentle exposure and positive experiences; don’t avoid the car (worsens anxiety). Cerenia for trips during puppy phase + desensitization.
Conclusion
Carsickness = motion + anxiety in most dogs. Cerenia is gold standard for motion sickness. Trazodone/gabapentin/Sileo for anxiety component. Acepromazine is no longer first-line – newer drugs are safer and more effective. Behavioral desensitization is the long-term solution that often eliminates medication need over time.
Frequently Asked Questions
What can I give my dog for motion sickness?
GOLD STANDARD: CERENIA (maropitant) – specifically labelled for canine motion sickness. Dose 8 mg/kg PO q24h starting 2 hours before travel; can give up to 4 consecutive days; NK1 receptor antagonist blocking nausea signal at brainstem; NO sedation; excellent safety profile. Veterinary prescription required. OTHER OPTIONS: 1) DIPHENHYDRAMINE (Benadryl) 2-4 mg/kg q8-12h – OTC, mild anti-nausea + sedative effect; less effective than Cerenia; avoid formulations with decongestants/acetaminophen; 2) METOCLOPRAMIDE 0.2-0.5 mg/kg q8h – prescription prokinetic anti-emetic; older drug; 3) DIMENHYDRINATE (Dramamine) 4-8 mg/kg q8h – OTC; older drug; less effective. WORKS BEST: Cerenia consistently outperforms older options. ADJUNCTS: empty stomach 4-6 hours before travel (or light meal); exercise before; cool car; facing forward; smooth driving; frequent breaks. SIDE EFFECTS Cerenia rare: GI upset occasional; safe combination with most other medications. PUPPY motion sickness often improves with vestibular maturation by 12 months – continue gentle car exposure to prevent anxiety component developing. CONSULT VET to get prescription and confirm appropriate for your dog.
Can I give my dog Benadryl for car travel?
YES – Benadryl (diphenhydramine) is SAFE and EFFECTIVE for mild travel anxiety + motion sickness in dogs, though less effective than newer prescription medications. DOSE: 2-4 mg/kg PO every 8-12 hours; for travel give 1 hour before departure. EXAMPLES: 5 kg Yorkie = 10-20 mg = 1/2 to 1 adult Benadryl tablet (25 mg); 10 kg dog = 20-40 mg; 20 kg dog = 40-80 mg = 2-3 adult tablets; 30 kg Lab = 60-120 mg; 40 kg dog = 80-160 mg. USE PLAIN diphenhydramine ONLY (Benadryl Allergy 25 mg tablets or generic equivalent); DO NOT use formulations with: 1) DECONGESTANTS (pseudoephedrine, phenylephrine – cardiac arrhythmia, severe toxicity); 2) ACETAMINOPHEN (Tylenol PM, etc. – liver failure); 3) ALCOHOL (some liquid forms); 4) Painkillers (Tylenol, ibuprofen). EFFECTS in dogs: mild sedation, mild anti-anxiety, mild anti-nausea (anti-histamine effect on vestibular system); 30-50% of dogs sedate noticeably, 30-50% no effect, 5-10% paradoxical agitation. WORKS BEST FOR: mild anxiety, mild motion sickness, short trips. MORE EFFECTIVE OPTIONS for moderate-severe: Cerenia (motion sickness gold standard), trazodone (anxiety), gabapentin (anxiety). SAFETY: very safe; rare side effects include excessive sedation, dry mouth, urine retention. TRIAL AT HOME first to assess individual response. COMBINE with: behavioral training, empty stomach before travel, cool car, smooth driving, restraint. If Benadryl insufficient for your dog, talk to vet about prescription options.
How can I help my dog with travel anxiety?
COMBINED MEDICATION + BEHAVIORAL approach works best. MEDICATIONS (vet prescription): 1) TRAZODONE 3-7 mg/kg PO 1-2 hours before travel – first-line for anxiety; SARI antidepressant; rapid onset; mild sedation; safer than acepromazine; 2) GABAPENTIN 10-25 mg/kg PO 2 hours before – anxiolytic + mild sedation; can combine with trazodone for severe; 3) SILEO (dexmedetomidine oromucosal gel) 125 mcg/m² applied to gum 30 min before – specifically labelled for noise aversion + anxiety; rapid onset; 4) CERENIA 8 mg/kg PO for motion sickness component (most anxious dogs also nauseous). OTC ADJUNCTS: ADAPTIL (DAP pheromone) spray on bandana or in car 15-30 min before; collar provides 4-week release; Benadryl 2-4 mg/kg as mild option. BEHAVIORAL DESENSITIZATION (long-term solution): Step 1 positive car associations 1-2 weeks (feed meals in stationary car, treats in car, no driving); Step 2 engine on no movement 3-7 days; Step 3 driveway and short trips ending at home 1-2 weeks; Step 4 positive destinations 2-4 weeks (parks, treat shops); Step 5 longer trips with breaks ongoing. 4-12 week investment reduces or eliminates medication need over time. TRAVEL DAY TIPS: exercise before (tired dog calmer); empty stomach 4-6 hours before; crash-tested harness (Sleepypod, Kurgo) or secured crate; cool 18-21C; facing forward; fresh air; smooth driving; frequent breaks every 1-2 hours; familiar blanket and toy; quiet environment (no loud music). SEVERE CASES: veterinary behaviorist consultation; combined medication protocols; longer behavioral programs. TRIAL DOSES AT HOME before travel day – individual response varies.
Why does my dog throw up in the car?
TWO MAIN CAUSES often coexisting: 1. MOTION SICKNESS – vestibular (inner ear) stimulation conflicts with visual input causing nausea; PUPPIES particularly affected because vestibular system not fully mature until 6-12 months; symptoms: drooling (often the first sign), lip-licking, repeated swallowing, restlessness, then vomiting; 2. ANXIETY – learned fear response from previous bad experiences (vet visits, getting carsick before, unfamiliar moving environment); symptoms: panting, shaking, whining, hiding, attempting to escape; can cause nausea through stress response. MOST DOGS HAVE BOTH components – addressing only one often fails. WHY PUPPIES ARE WORSE: 1) Vestibular system not mature; 2) Less car experience = anxiety; 3) Excitement (going somewhere new) causes vagal response; 4) Long fasting before vet visits combined with motion. CAN GET BETTER WITH AGE – many puppies grow out of motion sickness by 12 months as vestibular system matures, BUT only if anxiety component doesn’t develop in meantime. SOLUTIONS: 1) CERENIA (maropitant) 8 mg/kg PO 2 hours before travel – gold standard, vet prescription, specifically labelled for motion sickness, no sedation; 2) If anxiety component, add TRAZODONE 3-7 mg/kg PO 1-2 hours before; 3) Empty stomach 4-6 hours before travel (light meal or fast); 4) Cool car temperature 18-21C; 5) Facing forward (visual stabilization); 6) Fresh air; 7) Smooth driving; 8) Frequent breaks; 9) Crash-tested restraint; 10) BEHAVIORAL DESENSITIZATION over 4-12 weeks (gradually positive car associations). MOST CASES IMPROVE significantly with medication + behavioral approach. WORK WITH VET to get appropriate prescription and protocol for your dog. TRIAL DOSES AT HOME before travel day to assess response.
Is acepromazine safe for dogs to travel?
ACEPROMAZINE IS NO LONGER FIRST-LINE for travel anxiety. WHY IT’S FALLEN OUT OF FAVOR: 1) SEDATES WITHOUT TRUE ANXIOLYTIC EFFECT – dog physically unable to move or express but is still mentally anxious and stressed; appears calm but internal distress unchanged or worsened; 2) Can actually SENSITIZE dogs to noise and anxiety – each acepromazine experience may worsen anxiety over time; 3) UNPREDICTABLE response – some dogs paradoxically excitable; some dramatically sedated; 4) MDR1 SENSITIVITY in herding breeds – Collie, Australian Shepherd, Shetland Sheepdog, Old English Sheepdog, Border Collie, Long-haired Whippet, German Shepherd; can cause prolonged severe sedation, hypotension, even death at standard doses; 5) BRACHYCEPHALIC DOGS at higher risk – Bulldog, Frenchie, Pug, Boston, Boxer – hypotension and respiratory depression more pronounced; 6) CARDIAC EFFECTS – vasodilation can drop blood pressure significantly; problematic for dogs with cardiac disease, hypovolemia, debilitated. WHEN STILL USED: 1) Some clinicians still prescribe for VERY mild cases; 2) Pre-anaesthetic in healthy young dogs occasionally; 3) Combined with other agents in specific protocols. BETTER MODERN ALTERNATIVES: 1) TRAZODONE 3-7 mg/kg – first-line for anxiety; true anxiolytic effect; mild sedation; much safer profile; 2) GABAPENTIN 10-25 mg/kg – anxiolytic + mild sedation; very safe; 3) SILEO (dexmedetomidine oromucosal gel) – labelled for noise aversion + anxiety; controlled sedation; 4) CERENIA 8 mg/kg for motion sickness component; 5) ADAPTIL pheromone adjunct. TRAZODONE + CERENIA combination for most travel anxiety + motion sickness cases. TALK TO YOUR VET about modern alternatives – much better options now exist.
What’s the safest way to travel with my dog in the car?
USE A CRASH-TESTED RESTRAINT – this is non-negotiable for safety. WHY RESTRAINT MATTERS: 1) PROJECTILE FORCE in collision – 27 kg (60 lb) dog at 50 km/h (30 mph) = 1200 kg (2700 lb) of force; 2) DRIVER DISTRACTION risk from loose dog; 3) DOG ESCAPE in accident or sudden stop; 4) DOG INJURY 60-80% reduced with proper restraint (per crash testing). RESTRAINT OPTIONS (best to worst): 1. CRASH-TESTED HARNESSES – Sleepypod ClickIt and ClickIt Sport, Kurgo Impact, Ruffwear Load-Up – tested per CPS (Center for Pet Safety) standards; harness attaches to seat belt; allows some movement; ideal for most dogs; check fit per manufacturer instructions; 2. CRASH-TESTED CRATES/CARRIERS – Gunner Kennels, Variocage, Sleepypod Mobile Pet Bed – rigid crate secured to vehicle; ideal for travel-anxious dogs (den security) and small dogs; must be SECURED TO VEHICLE (not just sitting on seat); 3. ZIP-LINE STYLE TETHERS – simple but allow significant projectile motion; not crash-tested; better than nothing but not ideal; 4. UNRESTRAINED – DANGEROUS for dog, driver, passengers; can be illegal in some jurisdictions. OTHER SAFETY: 1) NEVER LEAVE DOG IN PARKED CAR – cars heat 10-20C above outside in minutes; dogs die of heat stroke quickly; brachycephalic breeds 3-4x higher risk; 2) BACK SEAT preferred – front seat airbags can injure or kill dog in collision; 3) BACK OF TRUCK BED UNSAFE – dog can jump out, fly out in collision, become projectile, suffer wind-related eye damage; 4) BACK OF SUV with crate or barrier appropriate; 5) WINDOW DOWN slightly OK but not enough for dog to put head fully out (eye injury risk from debris, ear trauma); 6) AIR CONDITIONING running; 7) TEMPERATURE 18-21C; 8) WATER available; 9) BREAKS every 1-2 hours; 10) CHECK COLLARS/HARNESSES daily on long trips; 11) ID TAGS current; 12) MICROCHIP registered with current contact info; 13) PET-FRIENDLY ROUTES planned; 14) EMERGENCY VET locations along route identified. CPS (Center for Pet Safety) maintains list of crash-tested products – centerforpetsafety.org.
Related PuppaDogs Calculators
Continue building your dog’s personalised care plan with these related PuppaDogs calculators:
- Dog Pregnancy / Whelping Due-Date Calculator
- Puppy Weight Predictor (Adult Weight Calculator)
- Heatstroke Risk Calculator for Dogs
- Bloat (GDV) Risk Calculator for Dogs
- Dog Life Expectancy Calculator (Breed, Body Condition, Lifestyle)
- Spay/Neuter Timing Calculator for Dogs (Breed-Specific)
References & Further Reading
The dosing ranges and safety information on this page are drawn from the following veterinary references. Always defer to your own veterinarian and the manufacturer’s label for your specific product.
- Conder GA et al. Maropitant (Cerenia) for the prevention of vomiting and motion sickness in dogs. J Vet Pharmacol Ther 2008.
- Hickman MA et al. Effects of acepromazine, butorphanol, and maropitant on emesis in dogs. JAAHA.
- Gilbert-Gregory SE et al. Trazodone for canine anxiety. JAVMA.
- Crowell-Davis SL, Murray T. Veterinary Psychopharmacology.
- Dexmedetomidine oromucosal gel (Sileo) – Zoetis veterinary product information for noise aversion.
- Mariti C et al. Behavioural problems related to travel in dogs.
- AAHA-AAFP Pain Management Guidelines.
- Mealey KL. MDR1 gene mutations – acepromazine sensitivity in herding breeds.
- Center for Pet Safety – crash-tested products list. centerforpetsafety.org
- Plumb DC. Plumb’s Veterinary Drug Handbook – maropitant, trazodone, gabapentin, acepromazine, diphenhydramine.
- Adaptil (DAP pheromone) – Ceva veterinary product information.
- PuppaDogs. Behaviour Screener, Anaesthesia Pre-Op Risk Calculator, BOAS Brachycephalic Hot Weather Safety. puppadogs.com.
















