Pharmacokinetics of Levamisole in healthy subjects and cancer patients

Abstract

Eleven healthy volunteers (six men, five women) and twelve cancer patients (six men, six women) were given single oral doses (2.5 mg/kg body weight) of levarnisole, an immunostimulant agent. In a second experiment eleven healthy et volunteers (six men, five women) and twelve cancer patients (six men, six women) were given single oral doses (5 rug/kg body weight) of levamisole. The levamisole concentrations in plasma (24 h blood sampling) were measured by gas chromatography after extraction. A mono-compartment open model was proposed, and some parameters were calculated. The main results from these two experiments are: the drug was absorbed well, the peak levels of levamisole in the plasma were reached after 1.0 -2.0 hrs and ranged between 0,8 l!g and 1.6 ug/ml with the 2.5 mg and 5 mg/kg body weight doses respectively (concentrations required in vitro to produce an immunological effect); the plasma half-life of levamisole calculated from the decline in the concentration curves varied between 3.3 hand 5.1 h; the absorbed fractions were 0.7 and clearance 310 ml/min; twenty-four hours after medication, the levamisole concentrations in plasma were only 6 % of the peak levels.The interindividual variability in the parameters seemed to be very important; and it may be concluded that the immunostimulant effect critically depends on the dose of the drug. A minimum effective plasma concentration is necessary to trigger its effects, on the other hand high concentrations may produce an immunosuppressive effect.

Oral bioavailability of levamisole in goats

“…On the other hand, k a showed a moderately rapid absorption from the gastrointestinal tract, with a mean value 12‐fold lower than in sheep and four‐fold lower than in goats and pigs (Galtier et al. , 1981, 1983), similar to those reported in humans (Luyckx et al. , 1982), rabbits (García et al.…”

“…, 1983) and dogs (Watson et al. , 1988) followed a one‐compartment open model, whereas in humans (Luyckx et al. , 1982; Kouassi et al.…”

Pharmacokinetic of levamisole in speckled surubimPseudoplatystoma corruscans

“…and 5.44 h (oral) (Fernández et al ., ); for goats t 1/2β = 1.44 h (oral) (Sahagún et al ., ); for swine, 9.3 and 6.9 h after oral and i.m. administration, respectively (Galtier et al ., ); for chicken, 5.7 h (El‐Kholy et al ., ); and for human; between 4.26 and 6 h (Luyckx et al ., ; Koussi et al ., ; Reid et al ., ). On the other hand, for rabbits, t 1/2β recorded were 1.42 h (Villanueva et al ., ) and 0.97 h (García et al ., ).…”

Randomized Controlled Trial of Levamisole Hydrochloride as Adjunctive Therapy in Severe Falciparum Malaria With High Parasitemia

“…In a previous study, the peak levels of levamisole in the plasma were reached after 1–2 hours [34]. The lack of a pharmacodynamic effect on sequestration can thus not be explained by inadequate absorption of levamisole after oral administration.…”