Compatibility of ondansetron hydrochloride and methylprednisolone sodium succinate in multilayer polyolefin containers.

PURPOSE: The compatibility of ondansetron hydrochloride and methylprednisolone sodium succinate in 5% dextrose injection and 0.9% sodium chloride injection was studied. METHODS: Test solutions of ondansetron hydrochloride 0.16 mg/mL and methylprednisolone sodium succinate 2.4 mg/mL were prepared in triplicate and tested in duplicate. Total volumes of 4 and 2 mL of ondansetron hydrochloride solution and methylprednisolone sodium succinate solution, respectively, were added to 50-mL multilayer polyolefin bags containing 5% dextrose injection or 0.9% sodium chloride injection. Bags were stored for 24 hours at 20-25 degrees C and for 48 hours at 4-8 degrees C. Chemical compatibility was measured with high-performance liquid chromatography, and physical compatibility was determined visually. RESULTS: Ondansetron hydrochloride was stable for up to 24 hours at 20-25 degrees C and up to 48 hours at 4-8 degrees C. Methylprednisolone sodium succinate was stable for up to 48 hours at 4-8 degrees C. When stored at 20-25 degrees C, methylprednisolone sodium succinate was stable for up to 7 hours in 5% dextrose injection and up to 24 hours in 0.9% sodium chloride injection. Compatibility data for solutions containing ondansetron hydrochloride plus methylprednisolone sodium succinate revealed that each drug was stable for up to 24 hours at 20-25 degrees C and up to 48 hours at 4-8 degrees C. CONCLUSION: Ondansetron 0.16 mg/mL (as the hydrochloride) and methylprednisolone 2.4 mg/mL (as the sodium succinate) mixed in 50-mL multilayer polyolefin bags were stable in both 5% dextrose injection and 0.9% sodium chloride injection for up to 24 hours at 20-25 degrees C and up to 48 hours at 4-8 degrees C.     

Stability of ondansetron hydrochloride in injectable solutions at -20, 5, and 25 degrees C.

The stability of ondansetron hydrochloride in 5% dextrose injection and in 0.9% sodium chloride injection when stored frozen, refrigerated, and at room temperature was studied. Solutions of ondansetron 0.03 and 0.3 mg/mL (as the hydrochloride salt) were prepared by adding 1.5 or 15 mg of the drug to 50-mL minibags containing 5% dextrose injection or 0.9% sodium chloride injection. All solutions were prepared in triplicate, and each container was tested in duplicate. Testing at the time of preparation and at each subsequent test interval included visual inspection of color and clarity, determination of pH, and a stability-indicating high-performance liquid chromatographic assay to measure the ondansetron concentration. Conditions assessed included storage at -20 degrees C for two weeks to three months, 5 degrees C for 7-14 days, approximately 25 degrees C for up to 48 hours, and various combinations of these conditions. The concentration of ondansetron in each solution remained above 90% of the original concentration at each observation time under all storage conditions. No changes in color or clarity were observed, and there were only minor changes in pH. Ondansetron 0.03 and 0.3 mg/mL in 5% dextrose injection or 0.9% sodium chloride injection was stable when stored (1) for up to three months at -20 degrees C, followed by up to 14 days at 5 degrees C and by 48 hours at 25 degrees C and (2) for up to 14 days at 5 degrees C, followed by up to 48 hours at 25 degrees C.     

Stability of ceftazidime (with arginine) and of cefuroxime sodium in infusion-pump reservoirs.

The stability of ceftazidime (with arginine) and cefuroxime sodium was studied after storage in infusion-pump reservoirs at freezing and refrigerated temperatures and subsequent simulated administration over 24 hours at near-body temperature. Polyvinyl chloride reservoirs and glass vials were filled with ceftazidime (with arginine) or cefuroxime sodium at various concentrations, diluted in sterile water. Three reservoirs each of ceftazidime 30 and 60 mg/mL and of cefuroxime 22.5, 30, 45, and 60 mg/mL were stored for various times and at various temperatures. Three glass vials each of ceftazidime or cefuroxime 30 and 60 mg/mL were stored for 30 days at -20 degrees C, followed by 4 days at 3 degrees C and 24 hours at 30 degrees C. Samples obtained periodically during storage and during simulated administration were analyzed with high-performance liquid chromatography. Both drugs maintained at least 90% of their initial concentration under all of the test conditions except simulated administration at 30 degrees C, during which degradation accelerated. In portable infusion-pump reservoirs, ceftazidime 30 and 60 mg/mL and cefuroxime 30 and 60 mg/mL were stable for 30 days at -20 degrees C followed by 4 days at 3 degrees C; ceftazidime 30 and 60 mg/mL was stable for 10 days at 3 degrees C; and cefuroxime 22.5 and 45 mg/mL was stable for 7 days at 3 degrees C. However, the drugs may need to be administered over less than 24 hours when the pump reservoir is worn on the patient's body.     

Stability of fentanyl citrate in 0.9% sodium chloride solution in portable infusion pumps

The stability of fentanyl citrate diluted with 0.9% sodium chloride injection for use in portable infusion pumps was studied. The commercially available injection containing 50 micrograms of fentanyl per milliliter was diluted to a concentration of 20 micrograms/mL. Twelve 100-mL portions of the dilute solution were placed in polyvinyl chloride infusion pump drug reservoirs; six were stored at 3 degrees C and six at 23 degrees C; three at each temperature were overwrapped with polypropylene-Mylar. Initially and after 5, 10, 20, and 30 days of storage, 1-mL samples were taken from each reservoir, inspected for color change and precipitation, and assayed for fentanyl concentration by high-performance liquid chromatography. Initially and on day 30, pH of the samples was checked. No precipitation or change in color or pH was observed. No substantial decrease in fentanyl concentration was found in either the wrapped or unwrapped samples at either temperature, although concentrations on day 30 in the samples at 23 degrees C were slightly lower than those at 3 degrees C. Under the conditions studied, fentanyl citrate solutions containing 20 micrograms of fentanyl per milliliter can be stored for 30 days in polyvinyl chloride reservoirs for portable infusion pumps.     

Stability of fluorouracil administered through four portable infusion pumps

The stability of fluorouracil in four portable infusion pumps under simulated infusion conditions was studied. Three commercially available fluorouracil aqueous solutions (50 mg/mL) were used. Samples adjusted to six pH levels were examined for precipitate. Drug reservoirs of four different portable infusion pumps were filled with 70 mL of each fluorouracil injection. Under conditions simulating actual use, the reservoirs were attached to the pumps and the solutions were pumped at a rate of 10 mL/24 hours over a seven-day period at 25 degrees C and 37 degrees C. Samples at the distal end of the extension tubing were collected hourly for the first 10 hours and at 12-hour intervals thereafter. Visual observations and pH determinations were made immediately. Drug concentrations were determined by reverse-phase high-performance liquid chromatography. Diethylhexylphthalate (DEHP) concentrations (the result of leaching from the plastic tubing and container) were determined by gas chromatography. In the pH study, precipitate appeared immediately in all fluorouracil injections below pH 8.52; precipitate was observed after two to four hours at pH 8.60-8.68. Under simulated infusion conditions, no apparent changes in concentration or pH were detected with any of the brands of drugs or portable infusion devices. At 25 degrees C, a fine white precipitate was observed in the extension tubing of all devices with the Roche brand of fluorouracil 48 to 96 hours after the pumping cycle began. The amount of DEHP leached from the drug reservoirs over the seven-day period was less than 1 ppm at both temperatures. All tested brands of fluorouracil injection were found to be stable under simulated infusion conditions over a seven-day period at 37 degrees C.     

Gas production of three brands of ceftazidime

Two sodium carbonate formulations of ceftazidime (Tazidime and Tazicef) and a new arginine formulation (Ceptaz) were evaluated for gas production and bubble formation within the drug reservoir and extension tubing of a portable infusion pump during a 24-hour delivery cycle. Triplicate samples of each brand of ceftazidime were studied under identical conditions. All formulations were constituted and diluted with sterile water for injection to a concentration of approximately 33 mg/mL, drawn into syringes, and expelled into infusion-pump drug reservoirs. Triplicate samples of degassed Tazidime and Tazicef were evaluated in the same manner. In one set of triplicate experiments, reservoirs for each formulation were attached to portable infusion pumps immediately after filling at room (23 degrees C) temperature and were programmed to deliver 25 mL over one hour every eight hours for a 24-hour delivery cycle. In a second experiment, reservoirs containing triplicate samples of each product were refrigerated (3 degrees C) for 24 hours before they were attached to the pumps for dose delivery. Visual observations were made for all pumping devices. In addition, multiple vials of each formulation were constituted, and the headspace pressure of the various formulations was monitored to compare the pressure build-up due to carbon dioxide. The presence of carbon dioxide was confirmed by gas chromatography. Pressure build-up due to carbon dioxide formation occurred in the ceftazidime sodium carbonate vials only. The sodium carbonate formulations required degrassing to reduce gas and bubble formation to a manageable level after constitution. Additionally, drug was lost because of spewing of some samples during withdrawal from the vial.(ABSTRACT TRUNCATED AT 250 WORDS)     

Stability of fluorouracil, cytarabine, or doxorubicin hydrochloride in ethylene vinylacetate portable infusion-pump reservoirs.

The stability of fluorouracil, cytarabine, and doxorubicin hydrochloride in admixtures stored in portable infusion-pump reservoirs was investigated. Admixtures containing fluorouracil 50 or 10 mg/mL, cytarabine 25 or 1.25 mg/mL, or doxorubicin hydrochloride 1.25 or 0.5 mg/mL in 0.9% sodium chloride injection or 5% dextrose injection were placed in 80-mL ethylene vinylacetate drug reservoirs protected from light, and 1-mL quantities were withdrawn immediately after preparation and after storage for 1, 2, 3, 4, 7, 14, and 28 days at 4, 22, or 35 degrees C. For each condition, three samples from each admixture were tested for drug concentration by stability-indicating high-performance liquid chromatography. The admixtures were also monitored for precipitation, color change, and pH. Evaporative water loss from the containers was measured. Fluorouracil was stable at all temperatures for 28 days. Cytarabine was stable for 28 days at 4 and 22 degrees C and for 7 days at 35 degrees C. Doxorubicin hydrochloride was stable for 14 days at 4 and 22 degrees C and for 7 days at 35 degrees C. No color change or precipitation was observed, and pH values were stable. Loss of water through the reservoirs was substantial only at 35 degrees C for 28 days. When stored in ethylene vinylacetate portable infusion-pump reservoirs, fluorouracil, cytarabine, and doxorubicin hydrochloride were each stable for at least one week at temperatures up to 35 degrees C. Cytarabine and doxorubicin hydrochloride showed decreasing stability at longer storage times and higher temperatures.     

Stability of morphine sulfate in portable pump reservoirs during storage and simulated administration

The stability of four concentrations of morphine sulfate injection in prefilled reservoirs for portable infusion pumps was studied after storage for 30 days at refrigerated and room temperature and after a three-day simulated administration period at body temperature. Thirty-milliliter samples of morphine sulfate injections in four concentrations--1, 5, 15, and 25 mg/mL--were loaded into a pump reservoir. The reservoirs were stored in the dark at 5 degrees C and 25 degrees C for 30 days. Samples were taken from each reservoir immediately after loading and after 7, 14, and 30 days of storage. The reservoirs were then connected to portable infusion pumps, which were run for three days at a flow rate of 0.4 mL/hr at 37 degrees C. The last sample was collected at the end of the three-day period. Samples were assayed for morphine sulfate content by high-performance liquid chromatography. The concentration of morphine sulfate increased up to 6% (for the 5-mg/mL sample) at refrigerated temperature and up to 16% (for the 15-mg/mL sample) at room temperature after 30 days' storage in the reservoirs. Evaporation of water from the reservoirs may have accounted for this phenomenon. No absolute relationship was found between the initial concentration of morphine sulfate and the percentage concentration increase after storage for 30 days. The change in morphine sulfate concentration before and after the three-day pumping period was not significant. Injectable solutions of morphine sulfate in concentrations ranging from 1 to 25 mg/mL are stable when stored at refrigerated temperature for 30 days in a prefilled drug reservoir.     

Stability of fentanyl citrate and bupivacaine hydrochloride in portable pump reservoirs

The stability of fentanyl citrate and bupivacaine hydrochloride in an admixture with 0.9% sodium chloride injection in portable pump reservoirs with or without overwraps was investigated. Twelve 100-mL samples containing fentanyl 20 micrograms/mL and bupivacaine hydrochloride 1250 micrograms/mL were placed in the plastic drug reservoirs, and 1-mL quantities were withdrawn immediately after preparation and at intervals during 30 days of storage. Six reservoirs were refrigerated (3 degrees C) and six stored at room temperature (23 degrees C); three at each temperature were placed in overwraps. All samples were observed for precipitation and for change in color or pH and were analyzed for drug concentration by high-performance liquid chromatography. No precipitation or change in color or pH was observed during the 30-day storage period. No loss of fentanyl or bupivacaine was detected in either the wrapped or the unwrapped samples. Fentanyl citrate and bupivacaine hydrochloride in 0.9% sodium chloride injection appear to be compatible, and admixtures containing the two drugs at the concentrations studied can be stored without overwraps for up to 30 days at refrigerated or room temperature without any significant loss of potency.     

Stability of intravenous admixtures of doxorubicin and vincristine

The stability of doxorubicin and vincristine in admixtures containing both drugs in 0.9% sodium chloride injection, 0.45% sodium chloride and Ringer's acetate injection, and 0.45% sodium chloride and 2.5% dextrose injection was studied. Doxorubicin hydrochloride was added to 30-mL quantities of each base solution to achieve initial doxorubicin concentrations of 1.40 mg/mL and to 0.9% sodium chloride injection to achieve concentrations of 1.88 and 2.37 mg/mL. Vincristine sulfate was added to each doxorubicin admixture to achieve vincristine concentrations of 0.033 and 0.053 mg/mL. All admixtures were protected from light and stored in polysiloxan bags that are used with portable delivery devices. Admixtures were kept at temperatures of 25, 30, and 37 degrees C. Samples withdrawn immediately after preparation and at 1, 2, 4, 7, 10, and 14 days were analyzed by high-performance liquid chromatography for content of each drug. The stability of doxorubicin was dependent on temperature and composition of the base solution. Analysis of data from the samples containing 0.45% sodium chloride and Ringer's acetate injection showed that doxorubicin concentrations were less than 90% of the initial concentration by 12 hours at 37 degrees C, 35 hours at 30 degrees C, and 62 hours at 25 degrees C, and visual changes occurred in all of these admixtures over the course of the study. Vincristine degradation also was most rapid in 0.45% sodium chloride and Ringer's acetate admixtures. Data analysis showed that concentrations of vincristine were less than 90% of initial after eight days at 25 degrees C, five days at 30 degrees C, and three days at 37 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)     

Stability of pibenzimol hydrochloride in commonly used infusion solutions and after filtration

The stability of pibenzimol hydrochloride was evaluated after reconstitution, after addition to several intravenous fluids, and after filtration. Vials containing pibenzimol hydrochloride 50 mg were reconstituted with 2.5 mL of 0.9% sodium chloride injection to 20 mg/mL. For determination of drug stability in intravenous fluids, vial contents were further diluted to 0.15 mg/mL by injection into glass containers and polyvinyl chloride (PVC) bags containing 250 mL of 5% dextrose injection, 0.9% sodium chloride injection, or lactated Ringer's injection. Pibenzimol concentrations were determined immediately after preparation and at various intervals after storage at 4-6 degrees C or 25 degrees C by means of a stability-indicating, high-performance liquid chromatographic technique. Vial contents were inspected visually for color changes, and pH was measured. Determinations were also made of the stability of pibenzimol 0.15 mg/mL in 0.9% sodium chloride injection after simulated infusions using a 0.22-micron filter set at 25 degrees C. All study solutions and admixtures retained more than 90% of the initial pibenzimol concentration. The greatest loss of drug (6-7%) occurred after 24 hours in lactated Ringer's injection in both glass and PVC containers and in 0.9% sodium chloride injection in PVC bags. No drug loss occurred as a result of filtration. Reconstituted pibenzimol hydrochloride and admixtures of pibenzimol in 5% dextrose injection, 0.9% sodium chloride injection, or lactated Ringer's injection in glass or PVC containers are stable for at least 24 hours at 25 degrees C. Filtration has no effect on stability.     

Stability of dobutamine hydrochloride in peritoneal dialysis solutions

The stability of dobutamine hydrochloride in peritoneal dialysis solutions at 4, 26, and 37 degrees C was determined. Dobutamine (as the hydrochloride salt) was added to dialysis solutions containing 1.5% or 4.25% dextrose to concentrations of 2.5, 5.0, and 7.5 mg/mL. Samples were stored at 4, 26, and 37 degrees C to mimic refrigerator, room, and body temperature, respectively. At 0, 4, 8, and 24 hours, the samples were analyzed in triplicate by stability-indicating high-performance liquid chromatography to determine the percentage of drug remaining. More than 90% of the drug was retained under all storage conditions in 1.5% dextrose dialysate containing an initial dobutamine hydrochloride concentration of 5.0 or 7.5 micrograms/mL. The mean concentration in the samples containing an initial dobutamine hydrochloride concentration of 2.5 micrograms/mL and stored at room temperature remained greater than 90% of the initial concentration for the first four hours and then decreased to less than 90%. Dobutamine was stable in 4.25% dextrose dialysate regardless of the initial concentration or the storage condition. Dobutamine hydrochloride 5.0 and 7.5 micrograms/mL in 4.25% dextrose dialysis solution was stable under all the test conditions. Dobutamine hydrochloride 2.5 micrograms/mL was stable in 1.5% dextrose dialysate for only four hours at room temperature.     

Stability of phenylephrine hydrochloride injection in polypropylene syringes.

PURPOSE: The stability of extemporaneously prepared phenylephrine hydrochloride injection stored in polypropylene syringes was studied. METHODS: Dilution of phenylephrine hydrochloride to a nominal concentration of 100 mug/mL was performed under aseptic conditions by adding 100 mg of phenylephrine hydrochloride (total of 10 mL from two 5-mL 10-mg/mL vials) to 1000 mL of 0.9% sodium chloride injection. The resulting solution was drawn into 10-mL polypropylene syringes and sealed with syringe caps. The syringes were then frozen (-20 degrees C), refrigerated (3-5 degrees C), or kept at room temperature (23-25 degrees C). Four samples of each preparation were analyzed on days 0, 7, 15, 21, and 30. Physical stability was assessed by visual examination. The pH of each syringe was also measured at each time point. Sterility of the samples was not assessed. Chemical stability of phenylephrine hydrochloride was evaluated using high-performance liquid chromatography. To demonstrate the stability-indicating nature of the assay, forced degradation of phenylephrine was conducted. Samples were considered stable if there was less than 10% degradation of the initial concentration. RESULTS: Phenylephrine hydrochloride diluted to 100 microg/mL with 0.9% sodium chloride injection was physically stable throughout the study. No precipitation was observed. Minimal to no degradation was observed over the 30-day study period. CONCLUSION: Phenylephrine hydrochloride diluted to a concentration of 100 mug/mL in 0.9% sodium chloride injection was stable for at least 30 days when stored in polypropylene syringes at -20 degrees C, 3-5 degrees C, and 23-25 degrees C.     

帕洛诺司琼联合地塞米松预防中度致吐化疗引起恶心呕吐的临床研究

目的 观察和评价帕洛诺司琼联合地塞米松预防中度致吐化疗方案所致恶心、呕吐(CINV)的临床疗效和不良反应.方法 60例患者采用中度致吐方案化疗,按随机抽样法随机分为帕洛诺司琼组和昂丹司琼组,各30例.帕洛诺司琼组给予盐酸帕洛诺司琼0.25 mg,第1天化疗前30 min静脉注射.昂丹司琼组给予盐酸昂丹司琼8 mg,化疗前30 min缓慢静脉滴注,连用3d.2组均联合地塞米松5 mg静脉注射.观察5d内恶心、呕吐等不良反应发生情况并作比较.结果 帕洛诺司琼组与昂丹司琼组急性CINV完全缓解率分别为80.0％ (24/30)和76.7％(23/30),有效控制率分别为93.3％(28/30)和86.7％(26/30),差异无统计学意义(P＞0.05);延迟性CINV完全缓解率分别为76.7％ (23/30)和63.3％(19/30),差异无统计学意义(P＞0.05),有效控制率分别为93.4％(28/30)和73.3％(22/30),差异有统计学意义(P＜0.05).2组不良反应发生率均较低,组间差异无统计学意义(P＞0.05).结论 帕洛诺司琼预防中度致吐化疗方案所致急性CINV 疗效与昂丹司琼相当,对延迟性CINV 的疗效优于昂丹司琼,不良反应程度较轻、安全性好.     

Compatibility of cefoperazone sodium and cimetidine hydrochloride in 5% dextrose injection

The compatibility of cimetidine hydrochloride and cefoperazone sodium in 5% dextrose injection stored at two temperatures was studied. Cimetidine hydrochloride and cefoperazone sodium were reconstituted or diluted with 5% dextrose injection to form an admixture with a cimetidine concentration of 2 mg/mL and a cefoperazone concentration of 5 mg/mL. The admixture was stored in 100-mL vented i.v. containers in the dark at 4 and 25 degrees C; three containers were stored at each temperature. A 2-mL sample was taken from each container after 0.5, 0.75, 1, 6, 12, 24, and 48 hours of storage and visually inspected, tested for pH, and assayed by a stability-indicating high-performance liquid chromatographic method. Triplicate studies were done for each storage condition. At both temperatures, drug concentrations varied by less than 5% during the study period. No color change, precipitation, or cloudiness was observed for any of the solutions under any of the storage conditions. Cefoperazone sodium 5.0 mg/mL and cimetidine hydrochloride 2.0 mg/mL in admixtures in 5% dextrose injection are stable for 48 hours at 4 and 25 degrees C.     

Stability of an analgesic-sedative combination in glass and plastic single-dose syringes

The stability of a combination of chlorpromazine hydrochloride (6.25 mg/mL), hydroxyzine hydrochloride (12.5 mg/mL), and meperidine hydrochloride (25 mg/mL) in glass and plastic syringes was studied. Syringes (glass 1.5 mL, plastic 3.0 mL) containing the combination drug solution were stored at 4, 25, and 44 degrees C. At 0,7,30,60,90,180, and 366 days after preparation, samples were visually inspected and tested for pH. Drug concentrations were determined by gas chromatography. No significant changes in drug concentration were apparent in any of the samples stored at 4 degrees C or 25 degrees C. Samples in both glass and plastic syringes stored at 44 degrees C turned yellow by day 30 and continued to darken throughout the study period. At the concentrations tested, chlorpromazine hydrochloride, hydroxyzine hydrochloride, and meperidine hydrochloride combined in glass or plastic syringes are stable for 366 days when stored at 4 degrees C and 25 degrees C. Degradation occurs at higher temperatures.     

Effect of glucose 5% solution and bupivacaine hydrochloride on absorption of sufentanil citrate in a portable pump reservoir during storage and simulated infusion by an epidural catheter

The stability of sufentanil (5 g/ml as citrate) in admixtures with glucose 5% or bupivacaine hydrochloride (2 mg/ml) in 100 ml polyvinyl chloride portable pump reservoirs was investigated during simulated infusion by an epidural catheter at 32°C for 48 h and during storage at 4°C and 32°C for 30 days. During both experiments a small decrease (<5%) in concentration of sufentanil and bupivacaine was observed. No loss of sufentanil or bupivacaine could be detected (in both experiments) in the portable pump reservoirs when stored at 4°C for 30 days. A significant decrease of sufentanil was observed when stored at 32°C after 30 days when diluted with glucose (9.2%) or in combination with bupivacaine (8.9%); also, the bupivacaine concentration decreased significantly (4.7%). It is concluded that sufentanil in portable pump reservoirs can be used under patient conditions at 32°C for 7 days when diluted with glucose 5% or 3 days in combination with bupivacaine hydrochloride.     

恩丹西酮注射液与异环磷酰胺在生理盐水中配伍的稳定性

目的：考察０℃～４℃,２５℃和３５℃下,恩丹西酮注射液与注射用异环磷酰胺在生理盐水中的配伍稳定性。方法：采用反相高效液相色谱法测定配伍后不同时间恩丹西酮与异环磷酰胺的含量,同时观察外观并测定ｐＨ值。结果：０℃～４℃,２５℃和３５℃下,两种药物在生理盐水中配伍后,２４ｈ内配伍液的外观澄明,未见气泡及颜色变化,ｐＨ值及含量均无明显变化。结论：两种药物在生理盐水中２４ｈ可以配伍使用。     

Stability and compatibility of reconstituted ertapenem with commonly used i.v. infusion and coinfusion solutions.

PURPOSE: The stability of ertapenem sodium in various commonly used i.v. infusion solutions and its compatibility with coinfusion solutions was studied. METHODS: Ertapenem was reconstituted with sterile water for injection and then diluted with various commercial i.v. infusion solutions to concentrations of 10 and 20 mg/mL. The solutions were stored in flexible polyvinyl chloride containers at 4 and 25 degrees C and in sterile glass vials at -20 degrees C. The drug's stability at 4 degrees C was monitored daily for up to 10 days, at 25 degrees C at appropriate hourly intervals for up to 30 hours, and at -20 degrees C. The daily for up to 14 days. Compatibility with the coinfusion solutions was monitored for up to eight hours at room temperature. Stability assays were conducted until the ertapenem concentration decreased by 10% or the corresponding degradation products exceeded the approved specifications. Ertapenem concentrations were determined by a stability-indicating high-performance liquid chromatography assay. RESULTS: Ertapenem was more stable in solutions stored at 4 degrees C versus 25 degrees C. Samples frozen at -20 degrees C showed extreme variability. Ertapenem 10 mg/mL was stable for a longer time than at the 20-mg/mL concentration. Ertapenem demonstrated the greatest stability in 0.9% and 0.225% sodium chloride solutions. CONCLUSION: Ertapenem sodium injection 10 and 20 mg/mL are relatively stable in sodium chloride injections and Ringer's solution when stored at 25 and 4 degrees C, but are unstable in mannitol and dextrose solutions. The drug can be coinfused with hetastarch, heparin sodium, and potassium chloride over several hours.     

Effect of procaine on the pH of buffered and unbuffered cardioplegic solutions

Changes in pH values were studied in two types of cardioplegic admixtures containing procaine 0.95 meq/L: an institutional formulation based on Ringer's injection and buffered with tromethamine injection 3.6%, and Plegisol (Abbott Laboratories) buffered with sodium bicarbonate injection 8.4%. Initial pH was measured in the buffered and unbuffered solutions before the addition of procaine and after the addition of 13 mL of procaine hydrochloride injection 2% or 260 mg of procaine hydrochloride powder (reference standard). Buffered 1-L admixtures containing procaine hydrochloride injection were stored (the institutional formulations in glass and the Plegisol admixtures in flexible plastic bags) at 3-5 degrees C or 25 degrees C. Plegisol admixtures were prepared with 10 mL (10 meq or 840 mg) of buffer as directed by the manufacturer or with 3 mL (3 meq) of buffer. Admixture pH was tested after various time intervals. Of the unbuffered solutions containing procaine, pH values were lower in Plegisol than in the institutional formulation. Of the procaine-containing buffered Plegisol solutions, only the admixture containing 3.0 mL of buffer and procaine prepared from powder had an initial pH in the acceptable range of 7.30-7.60. In all the stored solutions, pH changed rapidly; solution pH changed less under refrigeration. In the stored institutional admixtures, pH was acceptable for 96 hours at 3-5 degrees C and 24 hours at 25 degrees C. In the stored Plegisol admixtures to which 10 mL of buffer was added, pH was greater than 7.6 initially and continued to increase.(ABSTRACT TRUNCATED AT 250 WORDS)