Laser FAQ’s

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.
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.
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.
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.
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.
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.
It is not necessary to smell a burnt hair odor. The clinical endpoint practitioners should look for is peri–follicular edema.
There are no clinical studies showing that the DCD has ever caused Cancer.
There have been studies that have shown that too low of a fluence can stimulate limited hair growth.
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.
No due to the limited depth of penetration neither the organs or lymph nodes should absorb the laser light.
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.
Practitioners should avoid treating inside the orbital rim.
When using a scleral/corneal shield the eye is protected; however we advise that only experienced practitioners treat in this manner.
If light sensitivity is a concern then this should be discussed with the patient.
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.
There are several on the market. LMX–4 can be purchased over the counter, as well as EMLA is a similar option. Many accounts are having their own topical anesthetic compounded at their local compounding pharmacies.
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 patientʼs body. Some are performed under the chin, behind the ear or even on the buttocks.
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.
Candela recommends performing treatments for each indication separately.
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.
Hair can take up to two weeks to shed after treatment of the GentleLASE and nearly three weeks after treatment with the GentleYAG.
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.
The depth of penetration will be dependant on the laserʼs wavelength. The longer the wavelength, the deeper the penetration into the skin.
Candela recommends that each indication be treated individually and on different days.
It is advisable that each treatment be treated separately and on different days.
So long as the treatment is non–ablative, 2–3 hours is the recommended period of time.
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.
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.
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.
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.
Some patients may experience a phenomenon where all present hair follicles will become “in phase” and grow at the same time.
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.
While side effects are quire rare, the possibilities are erythema, edema, bruising, welting, hyper or hypo–pigmentation and blisters.
Common endpoints are erythema or redness, and edema or swelling.
Because each laser has their own specific wavelength, they each are attracted to different chromophores or targets.
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.
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.
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.
Absolutely. During a patientʼs consultation, it important to obtain information on any medication a patient may be taking. There is a list of these photosensitizing drugs here.
If there is a question regarding photosensitivity, or pigmentary changes while the patient is taking antibiotics, there are two course of action which the clinician can take:

  • Test spot
  • Abstain from treatment until the patient has completed their antibiotics.
  • Refer to Medications / Photosensitivity List which is found in this website.
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.
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.
It is not advisable to use lasers over areas that have been injected with filler. There are two lasers that have the ability to break down the filler very quickly. Smoothbeam: Do not use the Smoothbeam over filler. The Smoothbeam is attracted to water. Many of the fillers are hyaluronic acid (which is similar to water).

Smoothpeel: Do not use the Smoothpeel over filler. The Smoothpeel is attracted to water. Many of the fillers are hyaluronic acid (which is similar to water). GentleYAG: There is no clinical evidence that the GentleYAG breaks down filler, but the heat from the laser might contribute to quicker break–down.

GentleLASE: There is no clinical evidence that the GentleLASE breaks down filler, but the heat from the laser might contribute to quicker break–down.

Vbeam: There is no clinical evidence that the Vbeam family breaks down filler, but the heat from the laser might contribute to quicker break–down.

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.
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.