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Frequently Asked Questions About Laser Treatments

Do laser treatments hurt?

It depends on the type and location of treatment you’re getting.  Most clients think it feels like a rubber band snap. 

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, clients receiving treatment for benign pigmented lesions and other services 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 clients avoid ANY sun exposure, tanning beds, and sunless tanning products for at least 1 week prior to treatment. The only treatment that can be performed on clients with a tan is laser hair removal and should only be performed using the GentleYAG laser. The GentleYAG has no absorption of sunless tanning products, but we do prefer you don’t use it prior to your treatment.

What causes bruising?

Bruising, or purpura, is typically caused by energy being delivered into the skin too quickly, particularly with the 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 clients 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. 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 client responds differently therefore Jane Doe may need more treatments than Jill or John 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 clients need to keep these areas moist with an ointment and to avoid picking, scratching, or aggressively washing the area.

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. You may notice a difference with a different laser, such as the GentleLase.  Ten treatments are the average number of treatments it takes to remove the hair.

Can the DCD cryogen cause cancer?

There are no clinical studies showing that the DCD, the built-in cooling system that most of our lasers have, has ever caused Cancer.

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.  Hormones are the main element that activate hair to grow.

Does shaving make hair grow?

No.  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 photo rejuvenation properties. Heat created by these devices will stimulate the body’s 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 client.  Clients should be off of Accutane for at least 6 months prior to laser treatments. Other medications should be reviewed, 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.

Can the laser light flashing trigger migraines or seizures?

Yes, sometimes light sensitivity can stimulate these conditions.

What credentials are needed to perform laser treatments?

Each state has its own regulations on who can and cannot utilize a laser. In Colorado, there is no licensing requirement to operate a medical-grade laser.  However, a medical director (MD or DO) must be available for consultation.  We do have a medical director.

Are compression stockings required post leg vein treatments?

While compression stockings are common post sclerotherapy treatment, they are not necessary after treatment of leg veins.  However, they may help your legs feel better and speed up the healing time.

Can vessels on the chest and breast be treated?


What is a “good” topical anesthetic that works?

There are several on the market. We offer a 6% lidocaine product that we have formulated at a compounding agency.

How often do you need to replace the lenses, both in the Distance Gauges and the sliders?

Replacement of lenses is dependent on the practitioner keeping them clean. Preventing dust or hair residue from collecting on these lenses should allow them to last a great deal longer.

Is it okay if a client’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 client to experience welts. This is usually a good sign of an inflammatory response that can indicate efficacy of LHR treatments. If you experience welts, use a cold compress and/or an over the counter anti–inflammatory drug per standard of care if necessary.

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

In most cases, we would suggest that each indication be treated individually and on separated days. 1–2 weeks apart would be sufficient

Can you pulse stack for a vascular lesion if you don’t immediately see your clinical endpoint?

It is advisable to wait to see how the lesion is going to respond. Pulse stacking at too high of a fluence can result in pigmentary changes.

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. We wait to assess the reaction your skin has.  In some cases, we’re able to do two treatments on the same time.

Can you do treatments for both rosacea 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 client can receive for a particular indication?

There is no limit to the number of treatments you can receive. They must understand that there will be a limit on their improvement, and this should be discussed during the consultation.

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 clients 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 client be retreated for laser treatments?

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

Skin Tightening:  re-treatment can be about every 4 weeks.

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

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

Tattoo Treatments: re–treatment is dependent on the area being treated. The face and upper body are 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 dependent 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?

It depends on the laser treatment the client is receiving. 

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

It depends on the laser treatment the client is receiving. 

How long should a client 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 clients avoid sun exposure or tanning beds?

For most treatments with the GentleYAG, clients can experience sun exposure immediately.  But common sense should be practiced:  if there is a physical reaction, get out of the sun.

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 clients 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.

How can I get better efficacy when treating leg veins?

Wear compressions stocking for at least three days following the treatment.  Keep your legs elevated for as long as possible the first 48 hours after your treatment.  Use a good Vitamin K product to speed up the healing.

Is post treatment edema common for facial vascular anomalies?

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

What is the best aftercare for tattoo removal?

Post treatment care is very important after tattoo removal treatments. Clients should be advised to keep the area clean and dry. Application of an ointment and non–stick dressing is very important. Do NOT to pick, scratch or aggressively wash the area to prevent scarring.

Is it common for clients 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 clients shave their legs the day prior to having laser hair reduction treatments. This is done to alleviate any irritation to the lower legs (or whatever is being lasered). Shaving the day of treatment increases the likelihood of itching, swelling and red welts. It is unknown what the mechanism that causes these symptoms. Clients who experience this can apply cool compresses and take an antihistamine to resolve the issues.

Can clients exercise before or after treatment of leg veins?

Clients 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 client’s hair is growing thicker for several weeks after the treatment?

Some clients 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.

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 client will respond with this amount of efficacy. Clients should be told during consultation that results will vary from client to client.

What are the potential side effects from using the laser?

There may be temporary side effects, including but not limited to redness, swelling, and skin sensitivity.  Permanent side effects are quite rare, the possibilities include, but are not limited to   erythema, edema, bruising, welting, hyper or hypo–pigmentation and blisters.

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.

Tattoo Removal and Spots:  The laser light is attracted to the color and targets it.  The color is eradicated, and the color absorbs into the blood stream.

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.

Can clients who are taking antibiotics have laser treatments performed on them?

If there is a question regarding photosensitivity, or pigmentary changes while the client is taking antibiotics, there are two course of action which we can take:

  • Test spot

  • Abstain from treatment until the client has completed their antibiotics.

If a male client is taking performance enhancers, will it have an impact on the efficacy of their treatments?

It is possible that performance enhances might impact hair reduction treatments. If the performance enhancers have components which increase testosterone production, the increase in hormonal activity might interfere with efficacy.

What is the post treatment protocol for leg veins? Can I exercise? Can I drink alcohol? Etc?

In order to optimize leg vein treatments certain activities should be avoided:

  • Abstain from running, jogging, lifting weights for approximately 5 days.

  • Abstain from baths, hot tubs, saunas, long showers, or any activity which will make you sweat.

  • If your physician has recommended use of compression stockings, please follow their instructions for use.

  • Because alcohol can cause vasodilation, abstaining from alcohol is recommended for approximately 5 days.

How long does it take for hyper–pigmentation to resolve?

There is great variability in the timeframe hyperpigmentation resolves from person to person. The average amount of time can be from a few weeks to 1 year or longer.

Is there a protocol when using lasers over injectable fillers?

We do not use lasers over areas that have been injected with filler.


Can I do a laser treatment before in injectable filler?

Yes, in most cases.


What is the clinical endpoint for all procedures?

Laser Hair Reduction: Peri–follicular edema is the ideal endpoint. The darker/coarser the hair the more noticeable it is. For lighter finer hair, peri–follicular erythema is the endpoint

Vascular Lesions: Depending on the laser that is used, endpoints may be different. For vessels treated with the GentleLase, a vascular spasm occurs where the linear vessels will darken and return to normal over a matter of seconds. When treating with the GentleYAG, the vessels should virtually disappear, then bruise and swell.

Pigmented Lesions: Depending on the color of the lesion, a “snap” is generally heard during the treatment. The darker the lesion, the louder the “snap”. It is not uncommon for lesions to initially “frost over” and darker over a period of 5–10 minutes.  This darkness may scab and take several weeks to heal.

Skin Tightening/Wrinkle Reduction/Acne: Generally, erythema and slight edema are the clinical endpoints.

Tattoos: When treating tattoos, practitioners will notice a “popping” sound and frosting over the areas treated. This can last for several weeks.


Can clients that are pregnant be treated with lasers?

We do not treat pregnant women with lasers.

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