MedicinePlanet: Treating Motion Sickness

— -- Motion sickness is not actually a disease, but rather a collection of symptoms that can occur when your body, inner ear and eyes all send confusing signals to the brain.

When riding in a car, for example, your inner ear will sense motion, but your body is sitting still and your eyes only see the inside of the vehicle. These mixed signals confuse your brain and can lead to nausea, dizziness, lightheadedness and general malaise.

Most people can effectively manage their motion sickness with readily available OTCs (such as Bonine or Dramamine) or with simple herbal remedies such as ginger tea. Many report success with using specific acupressure points or homeopathic remedies.

But these measures are ineffective in some cases, and stronger medicine is needed. Fortunately, there are a number of prescription medications that can help with motion sickness, but travelers must be sure and tell their care providers if they are pregnant, nursing, have any serious medical conditions or are taking any other medications.

Prescription Motion Sickness Medications

Many people avoid becoming carsick or seasick by simply and steadily watching the road or the horizon. Some travelers, however, cannot alleviate their motion sickness by these methods, and their symptoms can be severe enough to cause real misery. While motion sickness is rarely life-endangering, the fear of spending several hours aboard a plane, bus, or car suffering acute nausea or vertigo might be enough to deter even the most ambitious traveler from taking a prolonged trip.

Fortunately, effective prescription medications are available. There are many to choose from, but they must be used with caution. Prescription drugs tend to be more powerful than herbs or OTC medicines, and can have significant and even dangerous side effects. These can vary tremendously, depending on the type of drug and the individual, and you should discuss them in advance with your health-care provider. Make sure your provider is also aware of any other medications that you are taking, both OTC and prescription, because drugs can occasionally interact unfavorably with each other. It’s a good idea to take a trial dose of the medication in the weeks prior to your trip in order to monitor any side effects that may occur.

Scopolamine

Scopolamine is derived from belladonna, and sold as a skin patch under the trade name Transderm Scop. It works by reducing the activity of nerve fibers in your inner ear, so that fewer confusing signals can be sent from there to your brain. The patch is worn behind the ear. One patch can prevent nausea and vomiting for up to three days; after that, a new patch must be applied if motion sickness is still a concern, such as on a long cruise or bus trip.

Scopolamine is usually effective, and problems with side effects are infrequent. About two-thirds of users report a dry mouth. Less commonly, temporary blurring of vision, eye pain, disorientation, memory disturbances, dizziness, restlessness, hallucinations or heart palpitations have been reported.

The drug’s main advantages are its ease of administration and its long-lasting effects, but its use is not advised for many people. Transderm Scop is not considered safe to use in children, who are particularly susceptible to the side effects of belladonna alkaloids in general (atropine is another medically useful derivative of this highly toxic plant). It should be used with caution in elderly individuals, who might have a similar sensitivity to its side effects. You should let your health care provider know if you are pregnant, nursing, have glaucoma or any other serious medical condition, and especially if you have ever had an allergic reaction to scopolamine.

Antihistamines

Antihistamines are a very broad class of drugs, primarily used to prevent or alleviate the symptoms of allergic reactions. These are the medications that most people take for hay fever. They have also been shown to be helpful in treating motion sickness. Each drug works by a slightly different mechanism, usually by interfering in some way with sensory-nerve transmission, thus reducing the amount of confusing information that gets to the brain.

Antihistamines come in many shapes and forms, from familiar OTCs such as Dramamine and Bonine to stronger drugs that are available by prescription only. Some, such as dimenhydrinate, diphenhydramine and meclizine, for example, are available in both prescription and OTC formulations. Because all drugs in this group take a while to begin to have an effect, if you use an antihistamine for motion sickness, take it at least one hour before you travel.

Drowsiness is a side effect common to all antihistamines, and you should avoid driving (and diving) once you have taken them. Other side effects occur less frequently and are similar to those that people experience with scopolamine.

Phenothiazine Derivatives

Medications that fall into this group are used to treat a wide range of ailments, including anxiety and certain psychoses. Some of them also have powerful anti-emetic capabilities, which means that they can both help prevent and alleviate nausea and vomiting. Two of the most common drugs used for motion sickness are promethazine (Phenergan, Promethegan) and prochlorperazine (Compazine).

These drugs are very effective for nausea, and if you happen to be in a situation where a doctor is available, as on many cruise ships, they can be administered as an injection — very helpful if you are vomiting and unable to keep down food, fluid or medication. Injection also gets the medication into your system quickly, so that it takes effect sooner than if swallowed. Promethazine can be taken as a preventive agent, usually 30 to 60 minutes before traveling.

The drawback is that phenothiazine derivatives are very powerful agents, and come with a host of potential side effects. While most people do well with them, especially if they are infrequently used, adverse reactions can range from a relatively benign dry mouth to serious blood conditions and neurological symptoms. Phenothiazine derivatives may be unsafe for pregnant and breast-feeding women, although the research is inconclusive at this point. Be sure to tell your provider about any other medications you may be taking; phenothiazine derivatives may not be advisable for you, as there are a number of medications with which these drugs interact unfavorably.

Before You Go:

See your medical care provider for a motion sickness medication prescription if OTCs, herbs or other non-prescription remedies don’t work for you. Take a trial dose of your prescribed medication sometime in the weeks before your trip. Take a dose an hour or so before departure, if your medication has a delayed onset of action.

Important Information: Prescription drugs tend to be more powerful than herbs or OTCs and must be used with caution. Make sure that your health-care provider is aware of other medications you are taking, and whether you have any medical conditions or are pregnant or nursing.

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