[Almitrine in therapy of chronic obstructive respiratory tract diseases with hypoxemia--a clinical multicenter study comparing 2 dosages].

In an 8-month prospective, placebo-controlled multi-centre trial involving 64 hypoxaemic COPD patients (mean +/- SD age, 64 +/- 8 years, paO2, 57 +/- 7 mmHg, paCO2, 41 +/- 6 mmHg), we compared the efficacy and acceptability of two different dosages of almitrine, 75 and 100 mg. 21 patients received continuous treatment with almitrine (75 mg), 23 sequential treatment (100 mg, one month of placebo after three months treatment), and 20 were in the placebo group. As defined by the inclusion criteria, none of the patients had clinical or subclinical signs of peripheral neuropathy. Clinical examinations, blood gas analyses and determinations of plasma almitrine levels were performed monthly. Patients underwent spirometry and detailed neurological examination upon entry and at the end of the trial. The percentage of drop-outs was considerably higher among patients under medication (59%) as compared to placebo (10%, p < 0.001) which was particularly due to impaired compliance in the almitrine groups. Comparing arterial paO2 or paCO2 over time by analysis of variance, there was no significant effect of medication on blood gases. However, in patients receiving 100 mg almitrine daily, paO2 was significantly increased vs. placebo after four and six months of treatment, and in patients receiving 75 mg almitrine, mean paCO2 was significantly lowered vs. placebo after four months of medication (t-test, p < 0.05). Neurological findings did not differ between treatments and over time. In conclusion, only certain individual patients may benefit from a treatment with 100 mg almitrine whereas the effect of the 75 mg dosage on paO2 did not differ from placebo.