[Clinico-therapeutic index and dosimetry of oral treatment with aromatic retinoid. A comparison of different dosages].

Computer evaluation of 70 patients with skin diseases treated with different dose schedules of oral aromatic retinoid over 3 months revealed that high initial dosage decreasing to maintenance levels, as previously recommended (75 mg leads to 50 leads to 35 mg; approximately 1 mg/kg/d leads to approximately 0.5 mg/kg/d), leads to earlier clinical response but has no further advantages compared to a low initial dose schedule (35 mg leads to 50 mg/d leads to 75 mg/d; approximately 0.5 mg/kg/d leads to approximately 1.0 mg/kg/d). After 3 months treatment, the therapeutic index was nearly the same in both groups. In the group with high initial dosage, however, the side effects also appeared earlier, were more numerous and some of them more intense. A slightly better clinical-therapeutic index was found in the group of patients treated with moderate doses varying between 35-60 mg/d (approximately 0.4-0.8 mg/kg/d). According to these results, high initial dosage of retinoid seems only recommended if a rapid clinical response is required, p.e. in severe pustular psoriasis. If long-term treatment is achievable and in patients with poor compliance, low initial dosage seems preferable. For most other cases we recommend moderate constant doses (0.5-0.85 mg/kg/d), increasing or decreasing the dose according to the clinical response and the individual needs of each patient. Computer analysis showed in addition, that classical side effects such as cheilitis, desquamation and hair loss were significantly dependent among other things on the total given dose; whereas, elevations of serum triglycerides were not clearly dose-dependent, appearing more frequently in males. In females, hair loss was significantly more frequent.