The aim of the present study was to investigate the effect of a combination of triiodothyroacetic acid (triac) and dehydroepiandrosterone (dhea) compared with triac, dhea or placebo alone on the corticosteroid-induced effect on collagen synthesis in humans. six healthy male human volunteers aged 40 to 65 participated. Four areas of abdominal skin were pretreated for 3 weeks with betamethasone valerate cream. The same areas were then treated with one of the following alternatives in the same cream vehicle: triac, dhea, triac + dhea and placebo for 2 weeks. then suction bubbles were raised in each of these areas with a vacuum pump. Bubble fluid from each area was collected and frozen until analysis. analysis of human procollagen amino terminal propeptide (pinp) in the suction bubble fluid was performed using a commercially available immunoassay kit (orion dia¬gnostics). This study showed for the first time that a combination of triac and dhea could effectively stimulate collagen synthesis in betamethasone valerate pretreated skin demonstrated by an increase in pinp, and that the combination was more effective than triac or dhea alone. This combination could be used to effectively treat skin atrophy in corticosteroid-induced skin atrophy. It could also be used to treat skin atrophy due to other circumstances such as sun damaged skin and skin atrophy due to advanced age. Another interesting application would be to combine triac and dhea with a potent corticosteroid to prevent corticosteroid-induced skin atrophy. If this combination is still effective in the treatment of eczema and psoriasis and without the risk of skin atrophy this combination will be further progress towards the use of potent topical corticosteroids.o objetivo do presente estudo foi investigar o efeito de uma combinação de ácido triiodotiroacético (triac) e desidroepiandrosterona (dhea) comparado com triac, dhea ou placebo sozinhos sobre o efeito induzido por corticosteróide sobre a síntese de colágeno