Unlike growth hormone, which causes irreversible hyperplasia, anabolic steroids cause hypertrophy, a reversible event. Oxandrolone is not ergogenic at labeled doses but athletes often use higher doses; athletic use should be discouraged due to the risk for dyslipidemia, potential hepatotoxicity, and other serious side effects. Due to the removal of the methyl group from the C-19 position, it has anabolic effects that are stronger than androgenic effects.Periodic assessment of liver function tests in all patients while on oxandrolone with drug discontinuation upon hepatic disease development is recommended. Baseline liver function tests and exclusion of preexisting liver disease are recommended prior to therapy initiation. Since most tumors are benign and androgen-dependent, hepatoma regression or growth cessation typically happens with oxandrolone withdrawal.The high-resolution mass spectrometry analysis was performed using a Synapt-G2Si instrument coupled to an Acquity M-class nano-LC system and equipped with an ionKey source (Waters Corporation, Milford, MA, USA). The amount of the active substance (OXA) in the tablets was determined by an LC-MS/MS method according to the previously published paper . Moreover, the developed SPE-UHPLC-MS/MS method is characterized by a possibility to identify and detect very low concentrations of oxandrolone in comparison to another previous published method . Viryus et al. were able to detect OXA in urine by high-resolution mass spectrometry up to 14 days after ingestion, but the volunteers were taking a dose of 10 and 20 mg per day during the 15 days before sample collection.The epi-oxandrolone metabolite was detectable 7 days after the drug administration with the maximum levels detected in urine between 20–40 h after the administration. The MRM chromatograms of OXA and its metabolite epi-oxandrolone in the urine taken 48 h and 9 days after the drug administration are depicted in panels C and D, respectively. This indicated no glucuronide and sulfate metabolic forms of OXA in the volunteer’s urine samples and, by that, no necessity for enzymatic hydrolysis as an additional sample preparation step. The optimized and successfully validated SPE-UHPLC-MS/MS method was applied to monitor OXA and its main metabolite epi-oxandrolone in the urine samples taken from a healthy volunteer after administration of 10 mg dose of OXA (one tablet Oxandrix). The recovery, calculated from the QC samples at three concentration levels, was higher than 88% (Table 4). Additional performance parameters brought similar positive conclusions for the developed method.The above stated and discussed results highlighted the analytical and application potential of the developed SPE-UHPLC-MS/MS method, and its usefulness for a reliable, fast, and sensitive monitoring of OXA and its main metabolite epi-oxandrolone in real human urine samples. A 10 mM formate at pH 6.2 was selected as the optimum loading solution enabling the removal of the highest amount of potentially interfering compounds from the matrix, and thereby, creating favorable conditions for the practical use of the developed SPE-UHPLC-MS/MS method (Figure 4A,B). The applicability of such a method for a study of renal OXA elimination and, by that, a common antidoping control, was verified via the analysis of urine samples taken from a healthy volunteer after peroral administration of one dose of OXA.The results obtained during the MS conditions optimization are clearly summarized in Table S1 (Supplementary Material). These findings were in good agreement with the previous published papers which deal with the analysis of OXA and its isobaric metabolite 17-epi-oxandrolone 27,29. These were further used as daughter ions in the triple quadrupole detection (see following sections). The solid-phase extraction (SPE), as sample preparation for an LC-MS/MS analysis of oxandrolone sulfate conjugates in urine, was described in 2016 by Rzeppa and Viet . The same group developed an HPLC-HRMS method enabling identification of OXA in the urine as long as two weeks after ending its 15-day administration . Several HPLC-MS methods have been developed for the monitoring of OXA and its metabolites in human urine .Completion of epiphyseal fusion leading to growth cessation does not occur with oxandrolone since it is not aromatized into substances with estrogenic properties. The risk of compromised adult growth is greater with oxandrolone use in younger aged patients. In general, the use of androgens in children should be undertaken only with extreme caution; growth suppression as a result of accelerated bone maturation may occur. Androgen therapy can result in hypoglycemia in patients with diabetes mellitus. Significant exposure to this androgen via breast-feeding may have adverse androgenic effects on the infant and the drug may also interfere with proper establishment of lactation in the mother.Concentration vs. time dependence was tested in the time interval of 4 h–12 days (after oral administration) to demonstrate the ability of the method to detect the renal elimination of oxandrolone from the human body. Periodic measurement of hemoglobin and hematocrit is warranted in patients receiving high doses of oxandrolone due to the potential development of polycythemia. Alternative methods to breastfeeding are recommended in lactating women receiving anabolic/androgenic therapy. Oxandrolone has anabolic potential that is between three and thirteen times more than that of testosterone and methyltestosterone. This section collects any data citations, data availability statements, or supplementary materials included in this article. anavar source reviews was obtained from all subjects involved in the study.The androgenic effects cover the development and maintenance of secondary sexual characteristics while the anabolic effect means protein synthesis promotion and skeletal muscle growth . Considering high reliability and a high degree of automation of the analytical process, the developed method is useful for routine use such as clinical or antidoping control. The interday precision and accuracy of the method were determined by analyzing the spiked samples over 3 consecutive days. The analytical measurement range of the creatinine in the urine matrix was from 250 to 35,400 μM. A Waters Acquity UPLC I-Class System was used in this study and configured with a sample manager, a column thermostat with two 2 position/6 port switching valves, and a binary solvent manager.Periodic lipoprotein monitoring is recommended due to the possible development of hypercholesterolemia consisting of decreased high-density lipoproteins (HDL) and increased low-density lipoproteins. Oxandrolone has the potential for teratogenesis (possible masculinization of the fetus) and, thus, is a pregnancy category X drug. Prostate cancer as a secondary malignancy or prostatic hypertrophy can develop during prolonged therapy with oxandrolone especially in elderly men. Because irreversible virilization of women can occur, oxandrolone should be discontinued with the development of voice deepening or hoarseness, hirsutism, acne, or clitoromegaly.