Peripheral arterial obstructive disease (PAOD) of the lower limbs affects 5% of the adult population. Uncontrolled arteriopathy is established due to a microcirculatory deficit, which may be present despite a good Winsor index and which leads to exhaustion of the functional microcirculatory reserve. The target of this study was to examine possible improvements in microvascular and tissue homeostasis by the administration of propionyl-L-carnitine (PLC). A total of 26 patients were enrolled in this study, aged 65 +/- 15 years; two males were diagnosed at stage IIA and 17 males and seven females at stage IIB PAOD. The main criterion of inclusion was the worsening of walking distance during the last month. In this study the duration of therapy was 33 days. PLC was administered in three flasks, each containing 300 mg in 250 cc saline by continuous infusion. The following parameters were measured before and after treatment: pain-free and maximum walking distance (measured on a treadmill at 3.2 km/hr with a gradient of 12%), recovery time from pain after maximum walking distance, ankle-brachial index by means of the Doppler apparatus, and evaluation of the microcirculation using capillaroscopy. The results showed that therapy with PLC was effective at restoring activity of skeletal muscle in ischemic conditions. In particular, capillaroscopy showed improvement in the angioarchitecture in the microcirculation fields, expressed as increased numbers of visible capillaries and diminution in the time of loss of sodium fluorescein marker. The clinical data showed increased walking distance and diminished time to recover from pain, and the clinical improvement correlated with improved microcirculatory function. From these preliminary data has emerged an indication of therapy with PLC for chronic obstructive arteriopathy of the lower limbs at stage II. Further studies with higher numbers of patients and more controlled variables are planned.