Dramamine(®) is an antihistamine medicine usually given to dogs to prevent vomiting and to control the symptoms of motion sickness. The most common active ingredient, dimenhydrinate, can be thought of as a weaker form of diphenhydramine (the main ingredient in most American Benadryl® allergy products) where 27 mg of diphenhydramine is roughly equivalent to the strength of 50 mg dimenhydrinate. Dimenhydrinate is actually a combination of diphenhydramine and a mild stimulant known as chlorotheophylline, which helps to prevent drowsiness.

Which formulation is best for my dog?

There are several different Dramamine medicines. The original formula, children’s formula and chewable tablets contain dimenhydrinate while the “All Day Less Drowsy” formula contains meclizine. All of these are safe and can be used to treat dogs, but owners should take care to avoid the “Non-Drowsy Naturals” tablets, as the amount of ginger contained within this product is too high.

Natural Recommendation: While over-the-counter medicines can help our nauseous pets they can also cause a wide range of nasty side effects, which is why you should use natural remedies whenever possible. We recommend Travel Eze, a high quality natural supplement which prevents motion sickness in dogs of all ages without the risks of Dramamine.
 

Recommended Dosage

 
Note: Please ask your vet for approval before giving any of these medicines to your dog.

Dimenhydrinate

When using tablets containing only this active ingredient we recommend a dosage of 1.9 – 3.6 mg/lb given by mouth as needed, leaving at least 8 hours between each dose.

Do not give more than 3 full doses per day. A typical dosage of 2 mg/lb is shown on the chart below.
 

Dimenhydrinate dosage chart
Dog’s Weight In Pounds: Dosage In Mg:

 
Some vets recommend 25 – 50 mg for any size dog given up to three times a day. The effects of the medicine usually last between 3 to 6 hours.

Meclizine

When using formulations containing meclizine as the only active ingredient you can administer 25 mg as needed once daily to control nausea and vomiting.
 
How long does it take to work?

For best results, tablets should be administered half an hour before its effects are needed (e.g. 30 minutes before a car journey to prevent travel sickness).
 

Example: A 50 pound dog could be given 100 milligrams of Dramamine containing dimenhydrinate every 8 hours, or 25 milligrams of Dramamine containing meclizine once daily.


How Safe Is It?

 
The tablets which contain dimenhydrinate or meclizine as the sole active ingredient are safe in the majority of cases and do not usually cause unwanted adverse effects.

It could be unsuitable if your pet has any of the following medical conditions:
 

  • COPD (sometimes)
  • Narrow-angle glaucoma
  • Bladder neck obstruction
  • Gastric outflow obstruction
  • High blood pressure
  • Enlarged prostate
  • Seizure disorders
  • Hyperthyroidism
  • Heart disease

 
Pets with COPD may be unsuitable for treatment if they are producing too much excess mucus.

Pregnancy/nursing: It may be safe for pregnant and nursing pets if used with caution, though high doses of meclizine have shown to be damaging to embryos and fetuses. Dimenhydrinate passes in small amounts through the milk but is unlikely to harm puppies.
 

Guidelines For Use

 
We recommend following these guidelines when treating dogs with this medicine:
 

  • Talk to your vet before using any of these medicines
  • Administer the medicine 30 to 60 minutes before travelling if relief from travel sickness is required
  • Tell the vet about any medical conditions your dog suffers from
  • Avoid giving these medicines alongside other anticholinergics
  • Do not use the ginger-based formulations

 
Each “Non-Drowsy Naturals” tablet contains 1000 mg of ginger which is far too much. If you want to use ginger you should buy generic pills and give 50 mg to medium and large dogs or 12.5 mg to small dogs three times daily (at most).
 

What Is It Used For?

 
Dramamine is usually used to prevent nausea, vomiting and motion sickness.
 

Side Effects

 
Dogs who are given the dimenhydrinate tablets could experience the following unwanted effects:

Most Common
 

  • Sedation
  • Dry mouth
  • Urine retention

 
Uncommon
 

  • Diarrhea
  • Vomiting
  • Weight loss

 
Pets who receive tablets containing meclizine could experience sedation. Rarely they can also experience a rapid heart rate and dry eyes or become hyperactive. Sedative effects often become less common with repeated use.

Overdose:

An overdose of dimenhydrinate could cause seizures, coma, hypoventilation or even death. Overdoses of meclizine will usually only cause increased sedation or hyperactivity, but very high amounts can cause seizures, hallucinations, urinary retention and a rapid heart rate. If you suspect an overdose you should immediately contact your vet or the ASPCA Pet Poison Helpline (800-213-6680). In most cases you will be asked to induce vomiting if the tablets were swallowed very recently.

Sources

Dr. R. Washabau
Plumb’s Veterinary Drug Handbook (sixth edition)