Are there any common side effects?

Most frequently reported side effects during a Thermage FLX treatment are mild to moderate pain. Typically, the discomfort is temporary during the procedure and localised within the treatment area. Rarely, patients have reported transient aching in the treatment area lasting up to several months. The most frequently reported side effects after a Thermage treatment are:

• Burns – The procedure produces heating in the upper layers of the skin, and may cause burns and subsequent blister and scab formation. There is a small chance of scar formation. Application of topical steroidal or antibiotic preparations may be of benefit. In the rare instance of a burn that results in a scar, the scar will probably be very small and respond readily to removal with a laser device.
• Surface Irregularities – Variously described as (localized) “small dents in the surface of the skin,” “rippling,” “ridging,” “waffle patterns”, or “fat loss” (covering a larger surface area). Frequently, surface irregularities are not evident immediately post-treatment, but show up later (1 or more months post-treatment). In most cases, Solta recommends that surface irregularities be monitored for a period of six months post-onset. Tissue fillers may be considered as a treatment option if the condition does not resolve on its own. Altered sensations – Described as “numbness”, “tingling” or “temporary paralysis”. Altered sensation typically resolves in a short period of time, but infrequently may persist up to several weeks. This adverse event is rare and, as is the case with an invasive facelift procedure, resolves over time without intervention.
• Lumps or Nodules – Subcutaneous nodules occurring primarily in the neck area may occur. It typically self-resolves within 1 or 2 weeks without adverse sequelae.
• Hyperpigmentation – Usually resolves over the course of time (within several months).
• Bruising – May occur in rare cases and typically dissipates within several days. Bruising may be more typically associated with the use of some injected anaesthetic agents (e.g. nerve blocks).
• Erythema – May occur in mild form and typically resolves within a few hours. However, on rare occasions, erythema has been reported to last longer (up to several weeks). Blanching usually resolves within twenty-four (24) hours. 
• Swelling – May occur and typically resolves within 5 days, but can persist up to several weeks. Application of cold compresses or gels immediately following the treatment may help to reduce the occurrence of this event.
• Itching – There have been occasional reports of a mild to moderate, transient itching sensation in the treatment area. Application of over-the-counter topical preparations may be helpful in relieving the symptoms.
• Herpes simplex – May result in rare cases in a treated area that has previously been infected with the virus. Reactivation of HSV is generally thought to occur most commonly in the perioral and genital skin areas after various stimuli.