FAQ - Laser Treatments

Is there any downtime after being treated with lasers?

Erythema (redness) and slight edema (swelling) are very normal after having a laser treatment and usually resolve after a day or two. However, patients receiving treatment for benign pigmented lesions and “laser peels” may experience micro crusting or even sloughing of the skin for a week to ten days.

If I’ve been out in the sun, use a tanning bed, or use sunless tanning products; can I be treated with a laser?

Because many of the lasers made by Candela have absorption by melanin/pigment, we advise that patients avoid ANY sun exposure, tanning beds, and sunless tanning products for at least 2 weeks prior to treatment and 2 weeks after. The only treatment that can be performed on patients with a tan is laser hair reduction and should only be performed using the GentleYAG laser. Still, patients should avoid sun exposure and tanning beds for 1 week prior to treatment and 2 weeks after. The GentleYAG has no absorption of sunless tanning products.

What causes bruising?

Bruising, or purpura, is typically caused by energy being delivered into the skin too quickly. Particularly with the Vbeam and GentleYAG for vascular anomalies. Also to be considered are medications or herbal supplements such as, ibuprofen, aspirin, vitamin E and fish oils. We also advise that patients avoid being treated soon after exercise. Vascular dilation creates more targets that may bruise.

What is the difference between fine and coarse hair?

The difference is the diameter. Finer hair has a lesser diameter than coarser hairs. This is important when determining the pulse duration of the treatment parameters. Remember we select our pulse duration dependent on the TRT or thermal relaxation time. The larger the structure, the longer the thermal relaxation time, thus the longer pulse duration required.

How many treatments are required?

The number of treatments required is dependent on several factors. First, what is the indication being treated? Hair requires more treatments than vascular lesions for example and what body area being treated for hair will also play a factor in number of treatments. Also, every patient responds differently therefore Jane Doe may need more treatments than Jill Doe.

What causes micro–crusting?

Micro–crusting is a result of heating the epidermis. When treating benign pigmented lesions, the object is to heat the abnormal pigment (dark spot) and as a result the pigment is cooked and turns a darker color. This result is the micro–crusting. Please remember that patients need to keep these areas moist with an ointment and to avoid picking, scratching, or aggressively washing the area.

Why have 3, 10, and 20 ms as pulse duration options on the YAG for LHR?

The pulse duration selection is dependent on the TRT, or thermal relaxation time of a structure. When treating hair, you should notice that hairs will have different diameters. The greater the diameter, the longer the thermal relaxation time, thus the longer pulse duration being required. Most practitioners will use 10ms for the first couple of treatments in most areas before moving to a shorter pulse duration of 3ms. The 20ms pulse duration is almost exclusively used for PFB (pseudo-follicular barbae).

Is it necessary to smell hair burning when using the YAG?

It is not necessary to smell a burnt hair odor. The clinical endpoint practitioners should look for is peri–follicular edema.

For stubborn hair, what can I do to be more effective?

As treatments progress, hairs that grow will usually be lighter, finer and maybe a little tougher to treat. Usually increasing the fluence to achieve greater absorption by these lighter hairs will be more effective. Always remember to judge a patients skin type to assist in determining an effective, but safe fluence.

Does light activate the hair to grow?

There have been studies that have shown that too low of a fluence can stimulate limited hair growth.

Does shaving activate an anagen cycle?

Shaving does not activate an anagen cycle. The mechanical action of shaving is to remove the hair above the skins surface. It has no effect on the hair follicle or surrounding structures.

Which Candela laser works best for wrinkles?

All of the lasers from Candela have some photorejuvenation properties. Heat created by these devices will stimulate the bodies own ability to produce collagen. What can be differentiated is the fact that different wavelengths have different depths of penetration into the skin. 1064nm would penetrate the deepest and 1450nm the shallowest. The rest fall in between.

Will the laser be harmful to organs and lymph nodes?

No due to the limited depth of penetration neither the organs or lymph nodes should absorb the laser light

Photosensitivity and Topical Meds: how long should medications and topicals be avoided prior to and after laser treatments?

It depends on the medication and the topical being used by the patient. Patients should be off of Accutane for at least 6 months prior to laser treatments. Other medications should be examined and a test spot be performed if there is any concern of an adverse reaction. Retinoids should also be ceased 3–5 days prior to laser treatment as they can create excessive redness. 

How close to the eye can be treated?

Practitioners should avoid treating inside the orbital rim.

How close to the eye can be treated with scleral/corneal shields?

When using a scleral/corneal shield the eye is protected; however we advise that only experienced practitioners treat in this manner.

Can the laser light flashing trigger migraines?

If light sensitivity is a concern then this should be discussed with the patient.

What credentials are needed to perform laser treatments?

Each state has its own regulations on who can and cannot utilize a laser. Please contact your state’s board of health or board of medical examiners.

Are compression stockings required post leg vein treatments?

While compression stockings are common post sclerotherapy treatment, they are not absolutely necessary after treatment of leg veins.

Can vessels on the chest and breast be treated?

Yes, but begin with lower fluences and perform a test spot to determine the appropriate energies.

What drugs, other than Accutane, would interfere with laser treatments?

There are a number of medications that are considered photo sensitizing. This list can be located here: (0920–23–0011) If light interacts with any of these medications, a test spot should be performed to judge the skin's reaction.

What is a “good” topical anesthetic that works?

There are several on the market. LMX–4 can be purchased over the counter. EMLA is similar option but requires a prescription. Many accounts are having their own topical anesthetic compounded at their local compounding pharmacies.

How often should test spots be performed, and where do you place them?

Test spots should be performed for considerations of both; how the skin is going to respond and what energy is going to be the most effective. Most practitioners will perform test spots on an inconspicuous area of the patient’s body. Some are performed under the chin, behind the ear or even on the buttocks.

When using white eyeliner to mark an area, can you treat directly over the lines?

Yes, since the eyeliner has no color, there should be no absorption by the laser light.

Is it okay if a patient’s skin welts up during the treatment? What does this mean and what should be done if it’s noticed?

It is quite common for a patient to experience welts. This is usually a good sign of an inflammatory response that can indicate efficacy of LHR treatments. Patient who experience welts can be given cold compresses and/or an over the counter anti–inflammatory drug per standard of care if necessary.

Can you treat both vascular and pigment components of poiklioderma on the same day?

We would suggest that each indication be treated individually and on separated days. 1–2 weeks apart would be sufficient

Can you do treatments for both hair reduction and wrinkle reduction the same day on the same area?

Candela recommends performing treatments for each indication separately.

Can you do treatments for both roseacea and wrinkle reduction the same day on the same area?

Candela recommends treating each indication separately.

Is there a limit of the total amount of treatments a patient can receive for a particular indication?

There is no limit of treatments a patient can receive. They must understand that there will be a limit on their improvement and this should be discussed during the patient consultation. If the patient and practitioner choose to continue with treatments, Candela is not aware of any contraindications in doing so.

What determines the setting for pulse duration?

The size of the structure will determine the setting for pulse duration. The larger the structure, the longer the pulse duration, thus the longer pulse duration required; and vice versa.

Why would I change from a larger spot size to a smaller one for laser hair reduction?

Most practitioners will begin treatments using the larger spot sizes. As treatments progress the necessity for higher fluence will require a drop down one spot size to achieve additional energy.

What spot size should be used on the upper lip?

The largest possible size should be used on the upper lip. Most patients cannot accommodate the 18mm spot size in this area; however the 15mm or the 12mm should be able to be used.

How long does it take for a hair to shed once it has been treated?

Hair can take up to two weeks to shed after treatment of the GentleLASE and nearly three weeks after treatment with the GentleYAG.

When should a patient be retreated for hair reduction? Pigment? Vascular?

Hair reduction: re–treatment will be dependant on the area being treated. The face, axilla, and bikini areas are treated every 4–6 weeks; Trunk (chest/back) every 8–10 weeks; and extremities 10–12 weeks.

Benign Pigmented Lesions: re–treatment is recommended at 4 week intervals.

Vascular Treatments: re–treatment is dependant on the area being treated. The face and upper body is typically every 4–6 weeks and for lower extremities or leg veins, every 10–12 weeks.

How deep does the laser penetrate into the skin?

The depth of penetration will be dependant on the laser’s wavelength. The longer the wavelength, the deeper the penetration into the skin.

Can you perform laser treatments and a chemical peel the same day?

Candela recommends that each indication be treated individually and on different days.

Can you perform laser treatments and microdermabrasion on the same day?

It is advisable that each treatment be treated separately and on different days.

How long should a patient wait before applying make up, deodorant, etc?

So long as the treatment is non–ablative, 2–3 hours is the recommended period of time.

When treating legs for hair reduction, do they need to be cleanly shaven?

Yes, all areas being treated for hair reduction should be shaved the day prior to treatment. Any hair that is above the surface of the skin will absorb light that is intended for the hair follicle.

How long before and after should patients avoid sun exposure or tanning beds?

For treatments with the GentleYAG, patients should avoid sun exposure and tanning bed for 1 week before and 1 week after treatment. For all other Candela devices, patients should avoid the sun for at least two weeks prior and two weeks after.

What should be applied to the skin post treatment?

There are many different things that can be applied to the skin after a laser treatment. Most common are aloe vera, cold compresses, and most importantly a 30+ spf sun block.

Should patients pre–treat an area prior to laser treatments for pigmented lesions?

It is not absolutely necessary; however if there is any concern regarding the surrounding skin response a hydro–quinone (bleaching cream) can be used.

Is post treatment edema common for facial vascular anomalies?

Yes, however not all patients will respond with excessive edema. For those patient's who react with edema, they can be given a cold compress and even an antihistamine, per standard of care, to alleviate the swelling. Patients should also be advised to sleep in a semi–recumbent position.

Is it common for patients having laser hair reduction on the lower legs to encounter itching, swelling, red welts, etc? Is this an allergic reaction to the DCD cryogen?

It is recommended that patients shave their legs the day prior to having laser hair reduction treatments. This is done to alleviate any irritation to the lower legs. Shaving the day of treatment increases the likelihood of itching, swelling and red welts. It is unknown what the mechanism that causes these symptoms. Patients that experience this can apply cool compresses and take an antihistamine to resolve the issues.

Can patients exercise before or after treatment of leg veins?

Patients should avoid exercise the day of treatment and for 5 days after the treatment of leg veins. Also to be avoided are excessively hot baths and showers, steam rooms or saunas, alcohol, and any medications that may thin the blood.

When performing hair reduction treatments, why does it sometimes seem like a patient’s hair is growing thicker for several weeks after the treatment?

Some patients may experience a phenomenon where all present hair follicles will become “in phase” and grow at the same time.

What is the difference between “purpura” and the bruises sometimes occurring after laser treatment using the Serenity Pro?

Purpura is a reaction caused by laser energy entering a vessel in a rapid fashion thereby rupturing the vessel allowing blood to escape creating the bruise. Any vascular discoloration caused by excessive suction of the Serenity Pro is similar to a hicky.

How much hair will remain after completing a series of treatment? In other words, is there a guarantee?

Unfortunately there are no guarantees in laser hair reduction. There are clinical studies showing improvement of up to 80–90% but that every patient will respond with this amount of efficacy. Patients should be told during consultation that results will vary from patient to patient.

What are the potential side effects from using the laser?

While side effects are quire rare, the possibilities are erythema, edema, bruising, welting, hyper or hypo–pigmentation and blisters.

What happens to the skin after treatment?

Common endpoints are erythema or redness, and edema or swelling.

Why are some lasers approved for some indications and other lasers approved for others?

Because each laser has their own specific wavelength, they each are attracted to different chromophores or targets.

What exactly is happening during the treatment? Hair? Vessels? Pigment? Etc?

Hair: The laser light is attracted to the melanin in the hair follicle; particularly in the bulb and bulge. Heat is collected there damaging the cells lining the hair follicle with the potential to also damage the vascular matrix preventing future hair from growing.

Leg Veins/Facial Telangiectasias: Depending on the modality in use the vessel will either be ruptured, coagulated, or luminal stenosis

Why is there a need for multiple treatments?

Due to the nature of the human body, it may take multiple treatments for improvement. For hair, there are several cycles of hair growth and a certain number of hairs may only be growing at a particular time. For vessels, they may need to be shrunk over a number of treatments. And wrinkle treatments are a result of the laser stimulating the body to produce or reorganize collagen.

What is the interval between laser treatments?

Typically most treatments are 4–6 weeks apart. However, depending on the indication being treated and where on the body the treatment is being performed. Treatments on the trunk should be done at 8–10 week intervals and extremities at 10–12 weeks.

There are many medications that may cause photosensitivity; is this important for patients having laser treatments?

Absolutely. During a patient’s consultation, it important to obtain information on any medication a patient may be taking. There is a list of these photosensitizing drugs at this link: http://www.candelalaser.com/practice360/basic/GeneralInformation/0920–23–0011.pdf

Can patients that are pregnant be treated with lasers?

ANSI Standards do not address this concern and Candela is not aware of any published studies on this subject. Since no known studies providing guidance on these risks are known, Candela recommends the following precautions: Defer the laser treatment during pregnancy; particularly laser treatments in the abdominal and pelvic areas. Other factors such as hormone changes, vascular proliferation, fluid retention and excessive hair growth may also affect procedure efficacy. Consultation with and approval by the physician or healthcare practitioner managing the pregnancy is advised.