UDC 615.212.7:616.15–071

The paper presents the results of studies of changes in the biochemical parameters of serum of rats with long-term use of nalbuphine and after its withdrawal. Because long-term use of opioids is known to lead to renal impairment, this study is relevant. There is little data in the literature on the dynamics of renal markers of renal impairment changes at a certain dose and duration and after opioid withdrawal. The aim of the study was to establish some biochemical parameters of the serum of rats with long-term therapeutic doses of nalbuphine and the late withdrawal of the drug. The study material was 45 white sexually mature male rats weighing 180–260 g. The serum determined total protein, urea, creatinine, calcium, phosphorus according to conventional methods. Statistical calculations were performed using RStudio v. 1.1.442 and R Commander v.2.4–4.At six-week administration of therapeutic doses of nalbuphine (subgroup N 6) the serum of rats was 64.40±3.57 g/l, at ten-week administration (subgroup N 10) – 74.90±3.81 g/l, at six-week administration followed by four-week withdrawal (subgroup N 6V4) – 65.60±1.58 g/l. Serum creatinine in subgroup N 6 was 107.90±7.40 μmol/l, N 10–94.28±2.98 μmol/l, N 6V4–96.19±1.26 μmol/l. The serum urea in subgroup N 6 was 7.62±0.73 mmol/l, N 10–8.90±0.90 mmol/l, N 6V4–5.71±0.13 mmol/l. Serum calcium in the subgroup N 6 was 2.39±0.09 mmol/l, N 10–1.98±0.08 mmol/l, N 6V4–2.82±0.08 mmol/l. The serum phosphorus index in subgroup N 6 was 2.11±0.12 mmol/l, N 10–2.04±0.11 mmol/l, N 6V4–2.12±0.07 mmol/l. Thus, prolonged use of nalbuphine leads to impaired nitrogen function of the kidneys and withdrawal of the drug – to partial restoration of this function. At six-week administration of nalbuphine and its subsequent cancellation, disturbance of reabsorption function of a kidney revealed after the tenth week of drug use is not observed.