Many Hawaii residents view boarding a plane with as much enthusiasm as they do a root canal, especially if they’re headed out of state. Even if they’re in first or business class, they know they’ll be in the air for at least five hours with no personal space, one of the disadvantages of living on islands 2,500 miles from the nearest coast.

Restricted movement causes poor circulation, which, in turn, can result in backache, neck pain and swollen feet and ankles. What can be done to make flying as comfortable as possible? Dr. Vernon Ansdell, a Kaiser Permanente internist who focuses on travel medicine, offers these seven tips:

>> Prone to motion sickness? Try to sit in the middle of the plane near the wings since that’s the most stable part of the plane. Candied ginger and ginger capsules are good remedies for the nausea, dizziness and fatigue brought about by this condition. Various prescription and over-the-counter medications also alleviate symptoms, including Bonine, Dramamine and Transderm Scop patches. Common side effects, however, are dry mouth, blurred vision and drowsiness. Before flying, try the medications to test for adverse reactions.

>> Ease ear pressure: Swallow often, chew gum, suck on candy, take oral decongestant pills (e.g., Sudafed and Clariton D) and use decongestant nasal sprays (e.g., Afrin and Neosynephrine) to relieve the increased inner ear pressure that occurs on takeoff and landing. There’s limited evidence that EarPlanes earplugs reduce the popping and clogging of the ears associated with flying.

>> Preventive care: Increased risk of illness results from sitting close to others for long periods in a confined space. Masks can become moist after about 30 to 60 minutes, making them ineffective filters for microorganisms. Instead, be sure you’ve had your annual flu shot before flying. Onboard, use hand sanitizers and wash your hands often. Because the air in planes is dry, skin moisturizers, eye drops and facial spritzers can help hydrate the body.

>> Limit intake of alcohol and caffeine: They promote dehydration. Also, be aware that the effects of alcohol intensify in the low-pressure cabins of aircraft. Carbonated sodas should also be avoided because they can cause abdominal distension, a sensation of abdominal pressure and bloating.

>> Deep vein thrombosis: Blood clots form in the veins of the legs, often as a result of immobility. These clots can break off and go to the lungs, causing sudden death.

The likelihood of this happening to a healthy person is rare. People with the following conditions, however, are at increased risk on flights that are longer than five or six hours: previous deep vein thrombosis or pulmonary embolus; obesity; pregnancy; varicose veins; blood-clotting disorders; recent leg fracture; recent serious illness, such as cancer or heart failure; and recent knee, hip, abdominal or other major surgery. Seniors and those on contraceptive pills or hormone replacement therapy also fall in the high-risk category.

Preventive measures include walking around the plane every hour (if the “fasten seat belt” sign is turned off, of course); staying well hydrated by drinking plenty of water and juice; using portable footrests to relieve pressure on leg veins; and wearing properly fitted compression stockings (Jobst, www.jobst-usa.com, is one recommended brand). Travelers deemed high risk should discuss prescription anticoagulant medicines with their doctor.

It’s usually best not to take sleeping pills when flying because response time might be delayed in case of an emergency, and the risk of deep vein thrombosis might be increased (due to lack of movement for a prolonged time).

>> Keep moving: Every few hours, do simple exercises while seated to improve circulation, relieve tension and stretch and strengthen muscles. These include knee lifts, back curls, neck rolls, spinal twists and foot flexes. For an instruction sheet email kphawaii.travelmed@kp.org.

>> Combat jet lag: Crossing time zones can disrupt your biological clock, including sleep patterns. Try to stay awake if you will arrive at your destination during the day. Go out in the sunlight and do some sightseeing, shop at a street market or stroll through a park. If you arrive at night, try to sleep even if you don’t feel tired.

If needed, take sleeping pills or sublingual melatonin tablets for the first few nights. Sublingual melatonin dissolves under the tongue and goes straight to the brain. Melatonin tablets that are swallowed metabolize in the stomach and liver before going to the brain. Thus, sublingual melatonin is more rapidly and predictably absorbed. It’s sold over the counter at most health food stores.