Most of Our Patients Experience No Adverse Effects
The majority of patients undergoing sclerotherapy experience no significant problems. Some minor side effects can occur, such as slight swelling at the injection site, which is a normal reaction and usually disappears within two or three days. Bruising around the treated area is also possible but typically fades within two to fourteen days without intervention.
In approximately one in five patients, particularly those with darker blue thread veins, staining may develop along the line of the treated vein. This appears as a dark brown area of pigmentation caused by haemosiderin, the iron component of blood cells. In most cases, this pigmentation resolves spontaneously over time, although treatment with laser may occasionally be required to disperse persistent staining.
If staining occurs after sclerotherapy or laser treatment, it is important to avoid sun exposure to the affected area. Sun‑tanning can cause the pigmentation to become permanent, resembling a tattoo. In a small number of cases, treatment may not be fully effective and the treated area may appear slightly brighter in colour than the surrounding skin. Despite these possibilities, the overall safety profile of sclerotherapy remains excellent, and most patients achieve a clear cosmetic improvement with minimal downtime.