To clear the body of unwanted hair, women have used just about everything: razors, hot wax and even chemical depilatories.

All of these solutions, while successful, need to be repeated to get results. Now, many medical spas and physicians offices are promising more permanent hair reduction with laser treatment. Providing a more long-standing solution, laser hair removal comes with some caveats, nonetheless.

We spoke to some experts to learn more about this treatment, including costs and what to expect from a procedure that promises to rid the body of unsightly hair.

Many areas of the body can be treated using laser hair removal, notes Melanie Grossman, MD, a clinical instructor of dermatology at Columbia Presbyterian Medical Center. She treats the face, ears, chin, chest, upper lip, legs, underarms, back and bikini area.

People with dark hair and fair skin are most likely to see success from laser hair removal. Patients with darker skin can benefit from laser hair removal, but a longer wavelength laser, such as a 1060 nm Q-switched laser, is needed, Dr. Grossman explains. But if you have white or light blonde hair, skip this procedure--it won't work, notes Raphael Darvish, MD, MBA, a dermatologist who performs laser hair removal at Skinpeccable, Brentwood, Calif.

Also don't be fooled completely by the term "laser hair removal": This technology promises permanent hair reduction, and won't totally rid the treatment area of all hair. Patients, however, should see up to 90 percent hair reduction, Dr. Darvish explains.

"It is probably the longest lasting treatment available," says Russell Kridel, MD, FACS, a Houston plastic surgeon who performs laser hair removal. "It may not totally remove hair in some instances but it can make the hair finer."

Lasers used for laser hair removal include a Q-switched laser or an Alexandrite. These technologies all work from the same principal: "The energy released by the laser light is absorbed into the pigment around the hair follicle," explains Russell Kridel, MD, FACS, a Houston plastic surgeon who performs laser hair removal. "The excess heat destroys the hair follicle. Because the follicle is dark compared to the surrounding skin, the surrounding skin is not damaged."

Laser hair removal isn't exactly pain-free, according to experts. "The procedure is tolerated well by most patients, as the laser functions so quickly that only a mild sting is felt," Dr. Darvish adds. In more sensitive areas, such as the bikini area, Dr. Darvish will opt for a topical anesthetic, but local anesthesia or pain medicine isn't required for the most part.

Treatment times vary depending on the amount, location and texture of the hair--which could add up to a number of visits. "You can do a facial or bikini area in 15-20 minutes, but a back can take longer, for example," Dr. Kridel explains.

It usually takes patients six to eight treatments to achieve substantial hair removal, and the treatments are spaced six weeks to 10 weeks apart due to growth phases, he adds. "Hair goes through growth cycles," says Dr. Kridel. "All the hair you treat is not in growth phase, so you have to do several treatments."

Laser hair removal comes with many advantages over other hair removal methods. Dr. Darvish notes large areas of the body can be treated, and the chances of scarring and pigmentation changes are minimal. "Laser hair removal is the most scientific approach and it is much faster than most other methods," Dr. Kridel says.

However, as with many procedures, there are some risks. The most normal reaction post-treatment is skin irritation or redness, but this occurrence will disappear within a few days, Dr. Darvish says. Aloe Vera, hydrocortisone or post-laser treatment creams can be used to calm this effect. "You will be notified during your consultation if you are susceptible to these side effects," he adds.

One precaution patients must take prior to treatment: "You must limit your sun exposure immediately prior to and after treatment. This will greatly minimize the risk of side effects," says Dr. Darvish.

If you have a suntan, you are at increased risk of pigmentary changes, including hypopigmentation; or lightening of the skin, or hyperpigmentation; a darkening of the skin.

Avoid getting the treatment in an area that has an active infection or where skin isn't in tact. Also, Dr. Grossman notes, laser treatment can locally reactivate a herpes simplex infection.

Even though your body may experience little pain from this treatment, you might feel some pangs when you open the wallet. Because laser hair removal isn't covered by insurance, the treatment will come at a cost that varies from city to city and also depends on the hair removal area and where you seek treatment.

Dr. Kridel says the lowest price ranges are between $100 for a small area of hair and $800 for a large area. However, "most patients find the treatment's lasting effects and reduced hair growth more than worth the cost," Dr. Darvish stresses.

Before seeing a specialist for a consultation, patients should do their research on laser hair removal and the professional they want to perform the treatment.

"Patients should consider who this person is," Dr Grossman stresses. "What training and credentials does he or she have? What kind of laser will the physician use?"

"To reduce your risks, choose a qualified, trained doctor who is trained in dermatology or a similar specialty," Dr. Darvish adds. "Your doctor should meet with you before the procedure and determine your treatment plan. If a physician's assistant or licensed nurse performs the procedure, your doctor should supervise and be available on-site during the treatments. Do not go to a spa, salon or clinic allowing nonmedical personnel to perform the procedure."

Some other points to consider prior to treatment, according to Dr. Darvish:

• Avoid sun exposure, sun tanning, tanning beds and tanning creams in the area to be treated for at least 3 weeks prior to your treatment.

• Avoid waxing, plucking or threading for at least 5 weeks prior to your treatment.

• Men should shave beard hair in treatment area.

• Shave the treatment area the night before or the morning of your treatment.

Let your laser hair removal professional know if:

• You have started oral antibiotics (Minocycline, Tetracycline, etc.) or Accutane.

• You are on a retinoid cream, such as Retin-A, Differin, Tazorac or Renova, on the areas to be treated.

• You are pregnant or are unsure if you are pregnant.

• You have an active cold sore. An active cold sore is a contraindication to laser treatments on the face.

Also, get your general practitioner involved first if you have an underlying health condition and are interested in laser hair removal or if hair is growing in a new or unusual place, Dr. Grossman adds. There could be an underlying cause, or this could be a reaction to a medication or a hormonal imbalance. In the case of a hormonal imbalance, you will continue to grow hair despite laser hair removal treatment, Dr. Kridel says.

Amanda Koehler is associate editor of ADVANCE, the parent company that produces this patient resource center.