Antihistamine Sea Sickness Remedy

Sea sickness is a form of motion sickness that arises when your brain gets conflicting signals from the parts of the body that normally detect and monitor movement--the eyes, inner ears, joints and muscles. Whether motion sickness is triggered by a ride in a car, train, plane or boat, according to MedlinePlus, the symptoms are generally the same: dizziness, nausea and vomiting. The most commonly used preventive medications are antihistamines.

What Causes It?

• An episode of motion sicknes--in this case, sea sickness--can occur, for example, if you are aboard a ship in a windowless cabin or public area. Although your inner ears might be sensing a good deal of movement on multiple planes, particularly if the seas are rough, your eyes are not witnessing evidence of motion. When the brain gets these contradictory signals, that can trigger one or more of the symptoms that characterize sea sickness. Although sea sickness is not serious and eventually will be resolved on its own, it can be extremely unpleasant and might even be accompanied by a sense of impending doom, according to the Centers for Disease Control and Prevention.

Be Prepared

• If you soon will be making a sea voyage or offshore fishing trip, visit your doctor and share with her your concerns about the possibility of sea sickness. Although she may give you some common-sense tips about avoiding the effects of motion sickness, she also probably will prescribe an antihistamine-based medication or suggest that you pick up an over-the-counter antihistamine formulation to prevent motion sickness. Be warned that such medications are helpful only if taken in advance of the onset of sea sickness, and they will be of no use once the symptoms hit.

Specific Antihistamines

• Particularly effective against sea sickness, according to the CDC, is a combination of the antihistamine doxylamine succinate with pyridoxine HCl. The combination is marketed in Canada as Diclectin and is available only by prescription. Although Diclectin is not available in U.S. pharmacies, the two active ingredients are sold in the United States, and your doctor can help to guide you in obtaining these medications and instructing you on appropriate dosing.

  In the "International Travel Health Guide," 14th Edition, Drs. Stuart Rose and Jay Keystone list a number of prescription antihistamines that have proven effective in preventing the nausea and vomiting of sea sickness. Most readily available is dimenhydrinate, sold over the counter as Dramamine. Take one or two tablets every four to six hours, starting one hour before the start of a boat trip.

  Available only by prescription, promethazine, marketed as Phenergan, is taken in doses of 25 mg twice daily. Take the first dose at least 30 minutes before your trip begins. Meclizine, marketed as Antivert and available only by prescription, is also effective against motion sickness. Take an initial dose of 25 to 50 mg, beginning an hour before departure, and repeat every 12 to 24 hours, as needed. The main side effect of these medications is drowsiness.