Compatibility studies of selected multichamber bag parenteral nutrition with fluconazole.

OBJECTIVE: Fluconazole (FLZ) is a drug widely used in the treatment of fungal infections including the treatment of immunocompromised patients, HIV-infected patients, and cancer patients. Critically ill patients often require the administration of drugs with parenteral nutrition (PN). The safety of this combination should be defined before the drug and PN are administered in one infusion line. This study aimed to determine the compatibility of FLZ with six selected multichamber bag parenteral nutrition. METHODS: FLZ solution for infusion was combined with PNs in appropriate proportions, considering most clinical situations resulting from different possible administration rates of the preparations. Samples were visually assessed, and pH, osmolality, turbidity, particle size (dynamic light scattering and light obscuration methods), and zeta potential were measured. These measurements were made immediately after combining the solutions and after 4 h of storage at 23 ± 1°C. RESULTS: FLZ combined with PNs did not cause changes observed visually. The turbidity of the samples was <0.4 NTU. The average particle size of the lipid emulsion was below 300 nm, and the PFAT5 parameter was ≤0.02%. The absolute value of the zeta potential of the PN + FLZ samples was higher for 5 out of 6 PN than the corresponding value for PN immediately after activation. Changes in pH and osmolality during 4 h of sample observations were within acceptable limits. CONCLUSION: Compatibility of the FLZ with six multichamber bag PN was confirmed. Hence, those preparations can be administered to patients in one infusion line using the Y-site.

Physical compatibility of colistin with analgesics during simulated Y-site administration.

DISCLAIMER: In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. PURPOSE: Special consideration is needed when intravenous drugs are administered simultaneously using a Y-site connector. This study aimed to investigate the physical compatibility of colistin with 6 analgesics at concentrations commonly used in clinical practice. METHODS: A pharmaceutical preparation of colistin was dissolved according to the manufacturer's instructions and diluted to a concentration of 1.5 mg/mL or 0.67 mg/mL (of colistin base). Simulated administration via Y-site infusion set was performed by mixing 5 mL of colistin solution with an equal volume of a solution of one of 6 intravenous analgesics. Infusion solutions of ibuprofen, ketoprofen, metamizole sodium, morphine sulfate, paracetamol, and tramadol hydrochloride were studied. For each analgesic tested, concentrates for injection were diluted with 2 solvents, resulting in 11 different combinations with each concentration of the colistin solution. The mixtures were visually inspected, and their turbidity was measured directly after mixing and at 3 consecutive time points (30, 60, and 120 minutes). Additionally, the pH of the mixtures was measured after 120 minutes and compared with the pH of the analgesic and the colistin solutions. RESULTS: During visual inspection with the unaided eye, no precipitate formation or gas evolution was observed in any of the tested analgesics except for sodium metamizole, where the yellow color of the solutions was observed. For samples containing the mixture of ibuprofen and colistin, the turbidity measurements revealed the presence of turbidity in the studied mixtures. The greatest change in pH relative to the value immediately after preparation was noted for combinations of ketoprofen and morphine sulfate with the tested antibiotic. CONCLUSION: Colistin was found to be incompatible with ibuprofen and metamizole sodium formulations. It should also not be combined with morphine sulfate due to the significant differences in the pH value of the preparations. The colistin 0.67 mg/mL and 1.5 mg/mL infusion solutions were physically compatible with ketoprofen, tramadol hydrochloride, and paracetamol.

Improving the Safety of Clinical Management of COVID-19 Patients Receiving Aminoglycosides and Parenteral Nutrition: Y-site Compatibility Studies.

PURPOSE: Aminoglycosides (AMGs) are broad-spectrum bactericidal antibiotics that can resolve bacterial infections co-existing with COVID-19 or exploit their potential antiviral activities. Patients presenting the most severe forms of COVID-19 due to escalating catabolism and significant lean body mass loss often require the concomitant administration of parenteral nutrition (PN) and antibiotics. The Y-site administration is one of the approaches allowing the co-administration of two intravenous medications in patients with limited vascular access. Our study aimed to investigate the compatibility of AMGs and selected commercial PN admixtures enriched in omega-3 fatty acids. METHODS: Gentamycin (GM), amikacin (AM), and tobramycin (TM) solutions for infusion were combined with Nutriflex Omega Special (NOS) and Smofkabiven (SFK). Three different volume ratios were investigated: 1:2, 1:1, and 2:1, simulating Y-site administration. Samples underwent visual examination and determination of the lipid emulsion particle size, zeta potential, and pH immediately after preparation and after four hours of storage at room temperature (22 ± 2 °C) with sunlight exposure. RESULTS: GM and AM combined with NOS in all studied ratios met the set-up acceptance criteria. The addition of TM to NOS in a 2:1 volume ratio and all tested AMGs to SFK in all studied combinations significantly influenced the stability of the oil-water system leading to the appearance of globules larger than 5 µm exceeding the pharmacopeial limit of 0.05% immediately after preparation or after four hours of storage. CONCLUSION: In conclusion, our study showed that NOS was less prone to destabilization of oil-in-water systems by AMGs than SFK. In justified clinical cases, due to the lack of appearance of precipitate or enlarged lipid droplets, the combined administration of GM and AM with the NOS could be considered, provided tested volume ratios of the drug and MCB in the infusion line are maintained. However, it should be noted that such an infusion may be associated with the risk of changes in the pharmacokinetics of the drug.

Y-Site Compatibility Studies of Ketoprofen with Parenteral Nutrition Admixtures for Central and Peripheral Administration.

Ketoprofen (KTF) is often used in hospital wards, especially in its intravenous form. According to the literature review, the compatibility of ketoprofen with parenteral nutrition (PN) admixtures has not yet been investigated. For this reason, we aimed to provide data contributing to physical compatibility to ensure the safe co-administration of these medications. In this study, we examined the compatibility of KTF with eight selected commercial PN admixtures intended for central (Lipoflex Special, Omegaflex Special, Kabiven, SmofKabiven) and peripheral (Lipoflex peri, Omegaflex peri, Kabiven Peripheral, Olimel Peri N4E) administration. The KTF solution for infusion was combined in three different volume ratios with studied PN admixtures reflecting the conditions in clinical practice. The evaluation of undesirable physical destabilization of oil-in-water system or precipitate formation involved the visual inspection and the determination of mean droplet diameter, zeta potential, pH, and turbidity changes. The results of compatibility of KTF with eight commercial PN admixtures showed that three of them: Kabiven, SmofKabiven, and Kabiven Peripheral, are incompatible with KTF and should not be concomitantly administered.

Structural and Spectroscopic Properties of Isoconazole and Bifonazole-Experimental and Theoretical Studies.

The paper compares the experimental FT-IR, UV-vis, and 1H NMR spectra of isoconazole and bifonazole with the density functional theory (DFT) calculations using different functionals. The results were compared with previously reported data related to their analogue, posaconazole. The analysis of calculated IR spectra with use of CAM-B3LYP (isoconazole) or B3LYP (bifonazole) functionals shows good accordance with the experimental IR spectrum. The best compatibility between the experimental and theoretical UV spectra was observed with the use of B3LYP or wB97XD functionals for isoconazole or bifonazole, respectively. The reason for the difference in the UV-vis spectra of isoconazole and bifonazole was discussed based on linear response time-dependent DFT and natural bond orbital methods. The calculated 1H NMR spectrum shows that the DFT formalism, particularly the B3LYP functional, give an accurate description of the isoconazole and bifonazole chemical shifts.

Toward Safe Pharmacotherapy: The Interplay between Meropenem and Parenteral Nutrition Admixtures.

Simultaneous administration of parenteral nutrition (PN) admixtures with intravenous antibiotics is a common clinical problem. Coadministration of drugs incompatible with PN admixture may affect its stability, especially in the context of lipid droplet size, which is a crucial parameter for patient safety. In the present study, we investigate the in vitro compatibility of meropenem (Meropenem 1000, MPM) with five commercial PN admixtures used worldwide: Kabiven, Olimel N9E, Nutriflex Lipid Special, Nutriflex Omega Special, and SmofKabiven. The appropriate volumetric ratios, reflecting their clinical practice ratios, were used to prepare the MPM-PN admixture samples. Physicochemical properties of MPM-PN admixtures samples were determined upon preparation and after four hours of storage. The pH changes for all MPM-PN admixtures samples did not exceed the assumed level of acceptability and ranged from 6.41 to 7.42. After four hours of storage, the osmolarity changes were ±3%, except MPM-Olimel N9E samples, for which differences from 7% to 11% were observed. The adopted level of acceptability of changes in zeta potential after four hours of storage (±3 mV) was met for MPM-Kabiven, MPM-Nutriflex Lipid Special, and MPM-Nutriflex Omega Special. The mean droplet diameter for all samples was below 500 nm. However, only in the case of Nutriflex Lipid Special and Nutriflex Omega Special, the addition of MPM did not cause the formation of the second fraction of lipid droplets. The coadministration of MPM via Y-site with Kabiven, Olimel N9E, and Smofkabiven should be avoided due to osmolarity fluctuations (MPM-Olimel), significant differences in zeta potential (MPM-Olimel, MPM-Smofkabiven), and the presence of the second fraction of lipid droplets >1000 nm (MPM-Kabiven, MPM-Olimel, and MPM-Smofkabiven). The assumed acceptance criteria for MPM compatibility of MPM with PN admixtures were met only for Nutriflex Lipid Special and Nutriflex Omega Special in 1:1, 2:1, and 4:1 volume ratios.

Compatibility of intravenous metronidazole with some all-in-one parenteral nutrition regimens.

OBJECTIVES: Supplementation of parenteral nutrition (PN) admixtures with other parenteral drugs may be desired especially in the case of polypharmacy and limited vascular access. Metronidazole (MTZ) is administered in surgical and critically ill patients often requiring concomitant nutritional therapy in the form of parenteral nutrition. The aim of the study was to evaluate the possibility of the concomitant administration of MTZ with PN admixtures from one container. METHODS: MTZ (1500 mg) was combined with six different PN admixtures and stored for 7 days before the simulation of administration. The mean droplet size (MDS) of the lipid emulsion, zeta potential, color, and pH of the tested samples were determined every 24 h. The content of MTZ was determined by the high-performance liquid chromatography method within the same time frames. RESULTS: PN admixtures supplemented with MTZ were characterized by a pH range from 6.19 to 6.38 and zeta potential range from -21.6 mV to -8.8 mV. For all samples the pharmacopeial criteria for intravenously administered emulsions were met: The visual inspection showed no sign of emulsion destabilization or precipitation, and the MDS was <500 nm. The MTZ content remained >90% of the initial value throughout the whole study period. CONCLUSIONS: Results showed the physicochemical compatibility and stability of PN admixtures supplemented with MTZ at the dose of 1500 mg. Such formulations can be stored at a temperature of 5°C for up to 7 d before administration to the patient.

Stability studies of parenteral nutrition with a high dose of vitamin C.

BACKGROUND: Postoperative administration of parenteral nutrition has become routine management in patients with gastrointestinal cancer. Providing patient the complete parenteral nutrition containing not only the macronutrients and electrolytes but also adequate doses of vitamins is a significant issue of nutritional therapy. The aim of the study was to develop parenteral nutrition containing a high dose of vitamin C (500 mg) and evaluate their stability. METHODS: Five compositions of parenteral nutrition were developed and stored for seven days in three different conditions. Physical stability studies including visual examination and determination of pH, size of lipid droplets (using dynamic laser scattering method), and zeta potential (using laser Doppler electrophoresis method) were performed for all studied parenteral nutrition with and without vitamin C immediately after preparation and after storage. The content of vitamin C was determined using high-performance liquid chromatography (HPLC) method. RESULTS: The addition of vitamin C to parenteral nutrition did not affect its physical stability. Degradation of vitamin C in parenteral nutrition occurred according to first-order kinetics reaction. The content of vitamin C remained above 90% of zero-time content within the first 24 h for each studied parenteral nutrition compositions stored at 4°C and 25°C with light protection. CONCLUSIONS: Vitamin C added to parenteral nutrition was unstable regardless of the storage conditions nor parenteral nutrition compositions. However, for the first 24 h, the content of vitamin C remained in the pharmacopoeial limit. Therefore, supplementation of parenteral nutrition admixtures with vitamin C in the dose of 500 mg is possible in the condition of administration to the patients within the first 24 h.

Clinical Nutrition of Critically Ill Patients in the Context of the Latest ESPEN Guidelines.

The group of patients most frequently in need of nutritional support are intensive care patients. This year (i.e., 2019), new European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines of clinical nutrition in intensive care were published, updating and gathering current knowledge on the subject of this group of patients. Planning the right nutritional intervention is often a challenging task involving the necessity of the choice of the enteral nutrition (EN) or parenteral nutrition (PN) route of administration, time of initiation, energy demand, amino acid content and demand as well as the use of immunomodulatory nutrition. The aim of this study was to specify and discuss the basic aspects of the clinical nutrition of critically ill patients recommended by ESPEN guidelines. Clinical nutrition in intensive care seems to be the best-studied type of nutritional intervention. However, meta-analyses and clinical studies comparing EN and PN and their impact on the prognosis of the intensive care patients showed ambiguous results. The nutritional interventions, starting with EN, should be initiated within 24-48 h whereas PN, if recommended, should be implemented within 3-7 days. The recommended method of calculation of the energy demand is indirect calorimetry, however, there are also validated equations used worldwide in everyday practice. The recommended protein intake in this group of patients and the results of insufficient or too high supply was addressed. In light of the concept of immunomodulatory nutrition, the use of appropriate amino acid solutions and lipid emulsion that can bring a positive effect on the modulation of the immune response was discussed.

Development, Validation, and Stability Assessment Application of RP-HPLC-DAD Method for Quantification of Ampicillin in Total Parenteral Nutrition Admixtures.

BACKGROUND: The administration of total parenteral nutrition (TPN) is a common procedure in intensive care units, where the concomitant use of other intravenous medication is frequently needed. One of the particularly dangerous complications for neurosurgical patients is meningitis, for which high doses of ampicillin (AMP) are used. In such cases, the addition of AMP to TPN admixtures would be a desirable procedure. Thus, the AMP determination method in TPN admixture was developed and validated. METHODS: An isocratic HPLC analysis was performed on a LiChrospher C18 end-capped column (250 mm, 4.6 mm, 5 µm) with a C18 pre-column (LiChrospher 100, 4 mm, 5 µm). The flow rate was 1.0 mL min-1 and the detection wavelength was 230 nm. System suitability parameters, such as capacity factor, numbers of the theoretical plate, asymmetry factor, as well as validation parameters, including method precision, accuracy, linearity, selectivity, and robustness, were set up. RESULTS: The method was shown to be linear, precise, accurate, specific, and robust, and it can be used for the quantitative analysis of AMP in TPN admixtures. CONCLUSIONS: The degradation of AMP in the TPN admixtures occurred according to first order kinetics. The degradation rate was high and dependent on the composition of the mixture and the storage conditions (t0.5 varied from 142.44 h to 300.45 h).

Physicochemical Compatibility and Stability of Linezolid with Parenteral Nutrition.

Patients referred to intensive care units (ICU) require special care due to their life-threatening condition, diseases and, frequently, malnutrition. Critically ill patients manifest a range of typical physiological changes caused by predominantly catabolic reactions in the body. It is necessary to provide the patients with proper nutrition, for example by administering total parenteral nutrition (TPN). The addition of linezolid to TPN mixtures for patients treated for linezolid-sensitive infections may reduce the extent of vascular access handling, resulting in a diminished risk of unwanted catheter-related infections. The compatibility and stability studies were conducted of linezolid in parenteral nutrition mixtures of basic, high- and low-electrolytic, high- and low-energetic and immunomodulatory composition. Mixtures containing linezolid were stored at 4⁻6 °C and 25 °C with light protection and at 25 °C without light protection for 168 h. In order to evaluate changes in the concentration of linezolid a previously validated reversed-phase HPLC method with UV detection was used. It was found that linezolid was stable at 4⁻6 °C in the whole course of the study whereas at 25 °C it proved stable over a period of 24 h required for administration of parenteral nutrition mixtures. The TPN mixtures demonstrated compatibility with linezolid and suitable stability, which were not affected by time or storage conditions.

Effect of Lipid Emulsion on Stability of Ampicillin in Total Parenteral Nutrition.

BACKGROUND: Ampicillin (AMP) is frequently administered parenterally in critically ill patients with meningitis or endocarditis. Many of them require parallel infusion of total parenteral nutrition (TPN) admixtures. The aim of the study was to determine the physicochemical stability of AMP in TPN admixtures. METHODS: AMP was added to two formulations of TPN admixtures differing in the lipid emulsion (Lipofundin® MCT/LCT 20% or LIPIDem®). Samples were stored at 4 ± 1 °C with light protection, and at 25 ± 1 °C with and without light protection to assess the impact of temperature and light on formulation stability. Every 24 h the pH, zeta potential, mean droplet diameter (MDD) of a lipid emulsion, and AMP concentration using HPLC method were determined. The assessment of stability and compatibility of TPN admixtures with vitamins and trace elements was carried out immediately after preparation and after 24 h of storage. RESULTS: The addition of AMP as well as vitamins and trace elements to the TPN admixtures did not affect their physical stability. An increase in the pH value of approx. 0.6 and reduction of zeta potential were observed. The MDD of the lipid emulsions was below the limit of 500 nm (dynamic light scattering (DLS) method) and no fat droplets greater than 525 nm were observed (light diffraction (LD) method). The content of AMP after the first 24 h was within the acceptable limit of 90% for TPN admixtures stored at 4 ± 1 °C and 25 ± 1 °C with light protection. CONCLUSIONS: The results showed that co-administration of AMP in the same bag with TPN admixture at the tested dose is possible when used ex tempore and with light protection.

The Interactions between Ciprofloxacin and Parenteral Nutrition Admixtures.

BACKGROUND: Co-infusion of parenteral nutrition (PN) and other drugs increases the risk of the interaction between drug and PN admixtures that can cause embolization of small blood vessels, resulting in potentially fatal consequences, including pulmonary embolism, or liver and retina vascular damage. The present study aimed to determine the compatibility between ciprofloxacin (CF) and eighteen compounded PN admixtures in order to assess the possibility of their co-administration via Y-sites. METHODS: CF and PN admixtures were mixed at two volume ratios (1:1 and 2:1) and potential interactions were examined using visual inspection, and measurements of pH, osmolality particle size, and zeta potential. The analyses were conducted immediately after sample preparation and after four hours of storage. RESULTS: The compatibility tests showed that the addition of the CF to the PN admixtures did not cause any color change or sign of destabilization in the fat emulsion. However, precipitation was observed in formulations containing higher CF concentrations and, in the case of lower CF concentrations, in formulations containing magnesium and calcium ions at a molar ratio of 2:1. CONCLUSIONS: The administration of CF and PN admixtures via the Y-site should be avoided or performed only with PN admixtures for which compatibility has been confirmed and the CF concentration in samples is 1 mg/mL at a molar ratio of magnesium to calcium ions of 1:1.

Thermo-, Radio- and Photostability of Perindopril Tert-butyloamine in The Solid State. Comparison to Other Angiotensin Converting Enzyme Inhibitors.

The main aim of this study was determination of thermo- radio- and photostability of perindopril tert-butyloamine (PER) therefore the efficiency and safety of the therapy could be maintained. A chromatographic method (RP-HPLC) had been validated before use to determine PER loss. The evaluation of stability properties of PER in solid state under the influence of isothermal condition, relative humidity - RH = 0% and 76.4%, exposure to 6 mln lux h and ionizing radiation generated by beam of electrons of 25-400 kGy was investigated. Studies pointed out that presence of moisture changes a kinetic model of PER degradation; lack of moisture in the air generates a first-order kinetic model of the reaction, increase humidity generates the autocatalytic model. PER proved to be resistant for ionizing radiation. It is possible to use radiation sterilization and decontamination (dose 25 kGy) with no significant loss of content. Investigation of PER photostability proved, that after exposure to 6 mln lux h physicochemical parameters are acceptable. Among all the ACE-I, PER has one of the shortest t0,5. PER should be stored in closed containers, protected from high temperature and moisture. PER is referred to be photostable and resistant for radiodegradation.

Formulation and characterization of EGCG for the treatment of superficial bladder cancer.

In the United States, the annual incidence of bladder cancer is approximately 70,000 new cases, with a mortality rate of approximately 15,000/year. The most common subtype (70%) of bladder cancer is superficial, namely hte non-muscle invasive disease form limited to the urothelium. The rate of progression and recurrence is up to 40 and 70%, respectively. Urothelial cell carcinoma of the bladder is typically treated with transurethral resection. The cancerous cells can float onto the adjacent epithelium, increasing the risk of recurrence. The standard of care is to offer adjuvant intravesical agents to reduce the risk of progression and recurrence. Current intravesical treatments are costly and are associated with special biohazard handling protocols. Patients are treated with intravesical therapy with bacillus Calmetter­Guerin (BCG) bacterium, or mitomycin C (MMC) following resection, both of which can cause moderate to severe side-effects which are rarely life-threatening. We previously examined the efficacy of epigallocatechin-3-gallate (EGCG) in comparison with MMC to prevent tumor cell implantation/growth in an animal model of superficial bladder cancer. Experiments revile that EGCG is slightly more effective than MMC at decreasing tumor cell implantation and consequent cancer growth in a bladder. This treatment requires the stringent sterile requirement of EGCG. EGCG can be unstable when sterilized at high temperatures. Thus, we evaluated two low temperature sterilization methods, such as ionizing radiation or the filtration method followed by freeze-drying. Both methods ensure the sterility of the sample; however, infrared and HPLC analysis revealed a slightly better stability of irradiated EGCG over the filtration method. The concentration of stable free radicals following irradiation was low, which are unlikely to exert any damaging effects to EGCG. Therefore, we consider that radiation will be the preferred method of EGCG sterilization, and that this may prove useful for the effective use of EGCG in the treatment of bladder cancer.

Determining whether curcumin degradation/condensation is actually bioactivation (Review).

Curcumin has been shown to exert therapeutic or protective effects against a variety of diseases, such as cancer, pulmonary diseases, neurological, liver, metabolic, autoimmune, cardiovascular diseases and numerous other chronic ailments. Over 116 clinical studies on curcumin in humans were registered with the US National Institutes of Health in 2015. However, it is mystifying how curcumin can be so effective in the treatment of many diseases since it has very low water solubility and bioavailability. Furthermore, curcumin is not stable under various conditions; its degradation or condensation into different bioactive compounds may be responsible for its biological activities rather than curcumin itself. In this review, we provide evidence of curcumin degradation and condensation into different compounds which have or may have health benefits themselves. Literature reviews strongly suggest that these molecules contribute to the observed health benefits, rather than curcumin itself.

Beta-Blockers: Current State of Knowledge and Perspectives.

It has been over half a century since propranolol, the first beta-blocker, was developed for medical treatment. Since that time a large number of compounds from this group have been synthesised and many are now in clinical use. The structure, function, pharmacokinetics, and mechanism of beta-blockers have been established. The possibilities for their use in treating different conditions continue to evolve. Since the discovery of later generation beta-blockers, such as carvedilol and nebivolol, the search for new compounds continues, and may include known substances with beta-blocking properties which could extend their therapeutic potential.

Identification of Radiodegradation Products of Acebutolol and Alprenolol by HPLC/MS/MS.

Two therapeutically active compounds from the group of ß-blockers, acebutolol (AC) and alprenolol (AL), in solid form were subjected to ionizing radiation emitted by a beam of high energy electrons from an accelerator with a standard sterilization dose of 25 kGy and in higher doses of 50-400 kGy. The effects of irradiation were detected by chromatographic methods (TLC, HPLC) and a hyphenated method (HPLC/MS/MS). No significant changes in the physicochemical properties of both compounds studied irradiated with 25 kGy were noted, but upon irradiation with the highest dose (400 kGy) the loss of AC and AL content determined by HPLC was 2.79 and 9.12%, respectively. The product of AC decomposition and the two products of AL decomposition were separated and identified by HPLC/MS/MS. It has been established that radiodegradation of AC and AL takes place by oxidation, leading to formation of the products of radiolysis, most probably alcohol derivatives of the ß-blockers studied. The additional product that appears on radiodegradation of AL is probably formed as a result of two simultaneous reactions: oxidation and CH2 group elimination.

The influence of ionizing radiation on itraconazole in the solid state.

The aim of this study was to investigate the ionizing radiation effects, in the form of an electron beam, on itraconazole (ITR) in the solid phase. It was found that the ITR, under the influence of a standard 25 kGy dose of radiation used for the sterilization of drug substances, decomposed at 0.4%. Moreover, a gentle change of colour and a decrease in melting point does not exceed pharmacopoeial standards causing that ITR can be sterilized by radiation method. The use of high 400 kGy radiation doses resulted in a 6.5% decomposition of the ITR and eight radiodegradation products were found. However, with the exception of differential scanning calorimetry (DSC), the X-ray diffraction, Fourier transform infrared spectroscopy (FT-IR) and ultraviolet-visible (UV-vis) methods showed no changes in the form and the morphology of the crystals. The structures of all those compounds were investigated. It was confirmed that the ITR decomposition takes place by dehalogenation (one of Cl atom elimination), the oxidation in isobutyl residue (beside the triazole ring) and C-O bond rupture.

The influence of ionizing radiation, temperature, and light on eplerenone in the solid state.

Eplerenone was subjected to the influence of ionizing radiation in the form of a high-energy electron beam (25-400 kGy), high temperature (90°C RH 0% and 60°C RH 76.4%), and light (6 mln lux h). An HPLC method was used to determine the content of eplerenone and to establish the impurity profile of all samples. As eplerenone was found to be a compound of great resistance to the above stress factors with the exception of high doses of ionizing radiation (≥ 200 kGy) when its degradation was above 1%, it is possible to sterilize eplerenone by radiation method with the standard dose of 25 kGy. Based on the analysis of impurities and degradation products, the mechanism of radiodegradation was demonstrated to differ from the mechanisms of photo- and thermodegradation. The observation that the DSC curves for the nondegraded and degraded samples of eplerenone were significantly different only under exposure to the electron beam confirmed the applicability of DSC for studies of radiolytic degradation of eplerenone.