It is reported that anti-mycotic agents are effective for the treatment of patients with atopic dermatitis. We studied the in vitro effects of anti-mycotics on T helper-1 and T helper-2 cytokine production in anti-CD3 plus anti-CD28-stimulated T cells from atopic dermatitis patients and normal donors. The amounts of interleukin-4 and interleukin-5 secreted by anti-CD3/CD28-stimulated T cells were higher in atopic dermatitis patients than in normal donors. Azole derivatives, ketoconazole, itraconazole, miconazole, and nonazole terbinafine hydrochloride, and tolnaftate reduced interleukin-4 and interleukin-5 secretion without altering that of interferon-gamma and interleukin-2 in anti-CD3/CD28-stimulated T cells from both atopic dermatitis patients and normal donors. The azole derivatives were more inhibitory than nonazole anti-mycotics. These anti-mycotics reduced the anti-CD3/CD28-induced mRNA expression and promoter activities for interleukin-4 and interleukin-5. The 3',5'-cyclic adenosine monophosphate analog dibutyryl 3',5'-cyclic adenosine monophosphate reversed the inhibitory effects of the anti-mycotics on interleukin-4 and interleukin-5 secretion, mRNA expression, and promoter activities. Anti-CD3/CD28 transiently (< or = 5 min) increased intracellular 3',5'-cyclic adenosine monophosphate in T cells, and the increase was greater in atopic dermatitis patients than in normal donors. The increase of 3',5'-cyclic adenosine monophosphate by anti-CD3/CD28 correlated with interleukin-4 and interleukin-5 secretion by anti-CD3/CD28. The transient 3',5'-cyclic adenosine monophosphate increase was suppressed by anti-mycotics, and azole derivatives were more suppressive than nonazoles. Azole derivatives inhibited the activity of cyclic adenosine monophosphate-synthesizing adenylate cyclase whereas terbinafine hydrochloride and tolnaftate enhanced the activity of 3',5'-cyclic adenosine monophosphate-hydrolyzing cyclic nucleotide phosphodiesterase in atopic dermatitis and normal T cells. These results suggest that the anti-mycotics may suppress interleukin-4 and interleukin-5 production by reducing 3',5'-cyclic adenosine monophosphate signal, and stress their potential use for the suppression of T helper-2-mediated allergic reactions.