The side effects that are applicable for standard sclerotherapy are also applicable to UGS. An American study of 62,236 UGS procedures looked at the side effects related to this procedure. Although this was a poorly conducted survey, because there was no standard method of treatment employed by all doctors, the incidence of side effects was still very low. They were: Matting 1.2%, Skin ulceration or necrosis 0.14%, Deep vein thrombosis 0.043%, Allergic reaction 0.02%, Arterial injection 0.003%, Pulmonary embolus 0.002%.
Side-effects do not differ from conventional sclerotherapy although the magnitude of certain complications when they occur, maybe greater. It does not appear from the above data that the rate of complications from UGS is unacceptably high. Indeed, it compares very favourably to the surgical option where a recent study showed the incidence of Deep Vein Thrombosis was 1.2% (28 times the incidence with UGS), Nerve injury 1.8%, Wound breakdown 3.6% and Wound inflammation 6.0%