Evaluation of carboxytherapy and platelet-rich plasma in treatment of periorbital hyperpigmentation: A comparative clinical trial.

Both PRP and carboxytherapy are relatively effective and their efficacy is comparable in treatment of POH. Carboxtherapy is simple and slightly more effective modality and well tolerated than PRP. We believe that both modalities are promising but not the ideal solutions of the POH problem which is caused by multifactorial etiology.