Stability of clindamycin phosphate with aztreonam, ceftazidime sodium, ceftriaxone sodium, or piperacillin sodium in two intravenous solutions

In admixtures containing clindamycin and either aztreonam, ceftazidime, ceftriaxone, or piperacillin in either 5% dextrose injection (D5W) or 0.9% sodium chloride injection (NS), the stability of each drug was studied. Each of the following combinations of drugs was added to 100-mL glass bottles of base solution: clindamycin phosphate 0.9 g and aztreonam 2.0 g, clindamycin phosphate 0.9 g and ceftazidime sodium 2.0 g, clindamycin phosphate 1.2 g and ceftriaxone sodium 2.0 g, and clindamycin phosphate 0.9 g and piperacillin sodium 4.0 g. Duplicate samples were prepared. Admixtures containing each single drug were also tested. Samples were visually inspected and tested for pH and drug concentration immediately after mixing and at 1, 4, 8, 12, 24, and 48 hours of storage in room temperature and light. Drug concentrations were determined by high-performance liquid chromatographic assay methods. Ceftriaxone retained greater than 90% of its original concentration for 24 hours in single-drug admixtures in NS, for eight hours with clindamycin in NS, and for one hour with clindamycin in D5W. Ceftazidime retained greater than 90% potency for 24 hours with clindamycin in D5W. In all other test admixtures, all drugs were stable for 48 hours. Under the conditions studied, clindamycin is compatible in the admixtures tested with aztreonam and piperacillin. Admixtures of clindamycin and ceftazidime in D5W should be used within 24 hours at room temperature. Clindamycin and ceftriaxone can be mixed in NS if administered within eight hours, but ceftriaxone is stable for only one hour in combination with clindamycin in D5W.     

Compatibility of clindamycin phosphate with cefotaxime sodium or netilmicin sulfate in small-volume admixtures

The stability and compatibility of clindamycin phosphate plus either cefotaxime sodium or netilmicin sulfate in small-volume intravenous admixtures were studied. Admixtures containing each drug alone and two-drug admixtures of clindamycin phosphate plus cefotaxime sodium or netilmicin sulfate were prepared in 100 mL of 5% dextrose injection and 0.9% sodium chloride injection in both glass bottles and polyvinyl chloride (PVC) bags. Final concentrations of clindamycin, cefotaxime, and netilmicin were 9, 20, and 3 mg/mL, respectively. All solutions were prepared in duplicate and stored at room temperature (24 +/- 2 degrees C). Samples were visually inspected, tested for pH, and assayed for antibiotic concentration using stability-indicating assays at 0, 1, 4, 8, 16, and 24 hours for admixtures in glass bottles and at 0, 8, and 24 hours for admixtures in PVC bags. No substantial changes in color, clarity, pH, or drug concentration were observed in any of the solutions. Clindamycin phosphate is compatible with cefotaxime sodium or netilmicin sulfate in 5% dextrose and 0.9% sodium chloride injections in glass bottles or PVC bags for 24 hours.     

Compatibility of clindamycin phosphate with aztreonam in polypropylene syringes and with cefoperazone sodium, cefonicid sodium, and cefuroxime sodium in partial-fill glass bottles

The stability and compatibility of clindamycin phosphate admixed with four beta-lactams, an experimental monobactam (aztreonam), and three cephalosporins (cefoperazone sodium, cefonicid sodium, and cefuroxime sodium), were studied. Aztreonam alone and the combination of clindamycin phosphate-aztreonam were prepared in duplicate polypropylene syringes. Each cephalosporin antibiotic as well as the three clindamycin phosphate-cephalosporin combinations were admixed in duplicate 100 ml partial-fill glass bottles containing either dextrose 5% in water or NaCl 0.9%. All solutions were examined, antibiotic concentrations were determined, and pH was measured at the time of admixture and 1, 4, 8, 12, 24, and 48 hours later. The solutions were maintained at room temperature under fluorescent lighting for the length of the study. Antibiotic concentrations were determined by drug-specific high performance liquid chromatographic assays. Significant instability or incompatibility was defined as a decrease in concentration of greater than ten percent relative to the initial concentration measured at the time of admixture. All antibiotics were stable for 48 hours. In the combination studies, clindamycin was stable for 48 hours, both in partial-fill glass bottles and syringes. Aztreonam, cefoperazone, cefonicid, and cefuroxime were also stable for 48 hours.     

Compatibility and stability of cefazolin sodium, clindamycin phosphate, and gentamicin sulfate in two intravenous solutions

We studied the compatibility and stability of clindamycin phosphate admixed with gentamicin sulfate and cefazolin sodium in small-volume diluents under specific storage conditions. In two replicate 100 ml dilutions of NaCl 0.9% injection and dextrose 5% (D5W) injection, clindamycin phosphate 900 mg was admixed with gentamicin sulfate 80 mg and cefazolin sodium 1 g. Drug concentrations were determined at the time of preparation and at 1, 4, 8, 12, 24, and 48 hours. Clindamycin and cefazolin were assayed by high-performance liquid chromatography and gentamicin was assayed by fluorescence polarization immunoassay. Visual inspections and pH determinations of each solution were performed at each assay time. Test solutions were maintained at constant room temperature and fluorescent lighting. Concentrations of clindamycin and gentamicin remained greater than 90 percent of the original concentrations throughout the study. Cefazolin concentrations dropped below 90 percent in D5W injection at 4 hours after admixture and at 12 hours after admixture in NaCl 0.9% injection. Visual analyses and pH changes revealed no significant changes. The combination of clindamycin phosphate 900 mg, gentamicin sulfate 80 mg, and cefazolin sodium 1 g in D5W 100 ml was found to be compatible for up to 4 hours. The duration of compatibility for these three drugs in 100 ml of NaCl 0.9% was 12 hours.     

HPLC-DAD考察头孢孟多酯钠与卡络磺钠在5%葡萄糖注射液和0.9%氯化钠注射液中的配伍稳定性

目的考察室温(25℃)下,注射用头孢孟多酯钠与注射用卡络磺钠分别在5%葡萄糖注射液和0.9%氯化钠注射液中的配伍稳定性。方法采用反相高效液相色谱法-二极管阵列检测器分别测定0～6 h内配伍液中头孢孟多酯钠和卡络磺钠的含量变化,同时观察配伍溶液的外观和测定其pH值。结果在室温(25℃)下、6 h内,配伍液外观无明显变化,但pH值和含量均变化明显。结论在室温(25℃)下、6 h内,注射用头孢孟多酯钠与注射用卡络磺钠在5%葡萄糖注射液和0.9%氯化钠注射液中配伍均不稳定。     

注射用头孢孟多酯钠在4种常用液体中的稳定性考察

目的考察注射用头孢孟多酯钠在25℃下与0．9％氯化钠注射液、5％葡萄糖注射液、10％葡萄糖注射液和5％葡萄糖氯化钠注射液4种常用输液液体配伍的稳定性。方法将注射用头孢孟多酯钠与输液配伍,采用高效液相色谱法测定头孢孟多酯钠的含量变化,并考察配伍液的外观和pH变化。结果注射用头孢孟多酯钠与0．9％氯化钠及5％葡萄糖氯化钠在室温下（25％）配伍,0～8h内其外观、pH值及含量无明显变化。而与5％葡萄糖注射液、10％葡萄糖注射液配伍稳定性欠佳。结论注射用头孢孟多酯钠与输液配伍时应选择0．9％氯化钠注射液或5％葡萄糖氯化钠注射液,不宜与5％葡萄糖注射液和10％葡萄糖注射液配伍。     

Stability of intravenous admixtures of aztreonam and cefoxitin, gentamicin, metronidazole, or tobramycin

The stability of aztreonam and cefoxitin, gentamicin, metronidazole, or tobramycin in intravenous admixtures containing aztreonam and one of the other drugs was studied. Admixtures of aztreonam and gentamicin, aztreonam and tobramycin, and aztreonam and cefoxitin were each prepared in four different concentrations in both 0.9% sodium chloride injection and 5% dextrose injection. Admixtures of aztreonam and metronidazole were prepared in two different concentrations using a commercially available solution of metronidazole 5 mg/mL in a phosphate-citrate buffer. One of each of these admixtures was stored at 25 degrees C for 48 hours and at 4 degrees C for seven days. At various storage times, 1-mL samples of the admixtures were tested for pH and assayed using high-performance liquid chromatography or fluorescence polarization immunoassay. The pH of all admixtures except admixtures of aztreonam and cefoxitin decreased only slightly during storage. Concentrations of aztreonam and tobramycin under both storage conditions decreased by less than 10%. Concentrations of cefoxitin and aztreonam decreased by more than 10% at 25 degrees C, and concentrations of gentamicin decreased by more than 10% under both storage conditions. Visual inspection of admixtures of aztreonam and metronidazole revealed an incompatibility between the two drugs, as evidenced by the appearance of a cherry-red color. Admixtures of aztreonam 10 and 20 mg/mL and tobramycin 0.2 and 0.8 mg/mL in 5% dextrose injection or 0.9% sodium chloride injection are stable for 48 hours at 25 degrees C or seven days at 4 degrees C. Admixtures of aztreonam 10 and 20 mg/mL and gentamicin 0.2 and 0.8 mg/mL in 5% dextrose injection or 0.9% sodium chloride injection are stable for eight hours at 25 degrees C and 24 hours at 4 degrees C. Admixtures of aztreonam 10 and 20 mg/mL and cefoxitin 10 and 20 mg/mL in 5% dextrose injection or 0.9% sodium chloride injection are stable for 12 hours at 25 degrees C and seven days at 4 degrees C. Aztreonam and metronidazole should be administered separately.     

注射用头孢孟多酯钠与注射用奥美拉唑钠序贯静滴的稳定性研究

目的：研究注射用头孢孟多酯钠与注射用奥美拉唑钠序贯静滴的配伍稳定性。方法：参考临床常用质量浓度,配制头孢孟多酯钠与5%葡萄糖注射液配伍溶液,再取该配伍溶液分别与不同体积的奥美拉唑钠溶液配伍。于0,0.5,1,2,3,4,5,6 h观察各配伍液的外观性状变化,测定pH值和不溶性微粒数,并采用HPLC法测定各配伍液头孢孟多酯钠的相对百分含量。结果：头孢孟多酯钠与5%葡萄糖注射液的配伍液在6 h 内外观无明显变化,与不同体积奥美拉唑钠配伍的配伍液随时间延长出现不同颜色的浑浊,在6 h内各配伍液中不溶性微粒数均符合规定,头孢孟多酯钠的相对百分含量略有下降。结论：在临床上,若注射用头孢孟多酯钠与注射用奥美拉唑钠静滴联用时,最好在两者之间先用0.9%氯化钠注射液清洗输液管道,完毕后再输注另一种药物,或者不将两者连续使用。     

Activity of antibiotic admixtures subjected to different freeze-thaw treatments

The freezing of antibiotic admixtures has been proposed as a potentially useful method by which the efficiency of admixture services might be improved. The time involved in thawing, however, has discouraged the implementation of this practice. This study describes a technique of thawing frozen antibiotic admixtures contained in minibags in commercially available microwave ovens. A quantitative microbiological agar gel diffusion assay was employed to determine the effect of such treatment on the antibiotic activity of the admixture. Admixtures containing cephalothin sodium, cefazolin sodium, cefamandole nafate, cefoxitin sodium, penicillin G potassium, ampicillin sodium, oxacillin sodium, carbenicillin disodium, and gentamicin sulfate in dextrose 5% solution were frozen at -20 degrees C for 30 days. The admixtures were assayed immediately before freezing, and again after either thawing technique: that is, upon exposure of the minibags to room temperature air or to microwave radiation. Assays were also performed 8 and 24 hours after thawing in order to assess antibiotic stability following each freeze-thaw treatment. It was discovered that, with the exception of ampicillin sodium, each of the antibiotics studied could be frozen and thawed as described without significant loss of activity, and were stable for 24 hours after thawing. The application of a freeze microwave-thaw technique to central admixture services can be seen as a cost-effective method of circumventing many of the problems associated with existing programs.     

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.     

Compatibility of ciprofloxacin injection with selected drugs and solutions.

The compatibility of ciprofloxacin injection with selected antimicrobials and aminophylline was studied. Ciprofloxacin, amikacin sulfate, aminophylline, clindamycin phosphate, gentamicin sulfate, and tobramycin sulfate were mixed separately in minibags containing 0.9% sodium chloride injection or 5% dextrose injection; admixtures were stored for up to 48 hours at either 4 degrees C or 25 degrees C. Ciprofloxacin was also combined separately with each of the other drugs and solutions and stored under the same conditions. In addition, ciprofloxacin was combined with metronidazole in ready-to-use mini-bags of the latter drug and stored at 25 degrees C. Drug concentrations were measured by fluorescence polarization immunoassay or high-performance liquid chromatography. All admixtures were also examined visually. Stability was defined as retention of at least 90% of the original drug concentration with no visual evidence of incompatibility. With one exception, drugs in all single-drug admixtures were stable for 48 hours. The drug concentration eight hours after amikacin was mixed in 0.9% sodium chloride and refrigerated was 89% of the original concentration. When ciprofloxacin was combined with gentamicin, metronidazole, or tobramycin, all of the involved drugs were stable for 48 hours. Compatibility of ciprofloxacin-amikacin admixtures depended on the fluid and storage temperature; all such admixtures were stable for at least eight hours. A precipitate formed immediately whenever ciprofloxacin was mixed with clindamycin and within four hours after ciprofloxacin was mixed with aminophylline. Ciprofloxacin injection was compatible with gentamicin, metronidazole, and tobramycin and incompatible with aminophylline and clindamycin. The compatibility of ciprofloxacin-amikacin admixtures depended on the i.v. solution and storage temperature.     

Stability of milrinone in 0.45% sodium chloride, 0.9% sodium chloride, or 5% dextrose injections

The stability of milrinone in 0.45% and 0.9% sodium chloride injections and in 5% dextrose injection in glass and plastic containers was studied. Admixtures containing milrinone 0.2 mg/mL were prepared in three 500-mL glass containers, three 500-mL polyethylpolypropyl copolymer plastic containers, and three 1-L flexible plastic containers of each solution. Milrinone content was determined by high-performance liquid chromatography at intervals during 72 hours of storage at room temperature; one sample of each solution and container type was protected from light. Duplicate assays of each sample were performed, and samples were observed for visual and pH changes. In all samples milrinone concentrations were more than 97% of the initial concentration. No changes in pH or appearance occurred. Milrinone at a concentration of 0.2 mg/mL is stable for 72 hours at room temperature in 0.45% and 0.9% sodium chloride injections and in 5% dextrose injection in glass or plastic containers.     

Stability of ranitidine hydrochloride at dilute concentration in intravenous infusion fluids at room temperature

The stability of ranitidine at low concentration (0.05 mg/mL) in five intravenous infusion solutions (0.9% sodium chloride, 5% dextrose, 10% dextrose, 5% dextrose with 0.45% sodium chloride, and 5% dextrose with lactated Ringer's injections) was studied. Admixtures were stored for seven days at room temperature in 150-mL and 1-L polyvinyl chloride infusion bags. Ranitidine stability in 0.9% sodium chloride injection and in 5% dextrose injection was also examined for up to 28 days, and these data were compared with data obtained at higher ranitidine concentrations (0.5-2.0 mg/mL). At intervals during the storage periods, color, clarity, and solution pH were examined and ranitidine content was determined by a stability-indicating high-performance liquid chromatographic assay. Ranitidine content remained greater than 90% of the initial concentration for more than 48 hours in all infusion fluids except 5% dextrose with lactated Ringer's injection. No visual changes or appreciable changes in pH were observed for any of the solutions. At the dilute concentration, ranitidine was markedly more stable after eight hours in 0.9% sodium chloride injection than in 5% dextrose injection. In 0.9% sodium chloride injection, ranitidine concentrations remained above 95% for up to 28 days, but drug concentrations in 5% dextrose injection fell below 90% after seven days. Stability in 5% dextrose injection improved as ranitidine concentrations increased from 0.05 to 2.0 mg/mL. Ranitidine (0.05 mg/mL) is stable for at least 48 hours at room temperature in all infusion fluids tested except 5% dextrose with lactated Ringer's injection.     

In vitro inactivation of tobramycin by cephalosporins

The in vitro inactivation of tobramycin when combined with each of six cephalosporins in samples of human serum was investigated. Each of six cephalosporins (cefazolin sodium, cefoxitin sodium, cefamandole nafate, moxalactam disodium, cefoperazone sodium, and cefotaxime sodium) was added to human serum samples containing tobramycin sulfate 8 micrograms/mL to produce final cephalosporin concentrations of approximately 250 and 1000 micrograms/mL. Duplicate solutions were prepared and stored at either 0 or 21 degrees C. Solutions containing tobramycin 8 micrograms/mL alone and with carbenicillin disodium in four concentrations were prepared as controls. Samples were assayed using a fluorescence polarization immunoassay (TDX) at 0, 2, 4, 8, 12, 24, and 48 hours to determine tobramycin concentration; two of the carbenicillin-tobramycin solutions were frozen immediately for assay 53 hours later. Tobramycin concentrations in the admixtures were compared with those in tobramycin reference samples. At both temperatures, samples containing tobramycin with cefamandole 250 micrograms/mL or cefotaxime 250 micrograms/mL showed less than 10% inactivation of tobramycin for at least 48 hours. At 0 degrees C, tobramycin retained greater than 90% activity when combined with cefoperazone 250 and 1000 micrograms/mL. In samples containing cefazolin 250 micrograms/mL at 0 degrees C and cefoperazone 250 micrograms/mL at 21 degrees C, tobramycin was stable for 24 hours. Only samples containing moxalactam stored at 21 degrees C showed greater than 16% inactivation of tobramycin at 48 hours. Under these study conditions, tobramycin is only moderately inactivated in vitro when combined with clinically achievable concentrations of the tested cephalosporins (excluding moxalactam) and then stored for up to 48 hours.(ABSTRACT TRUNCATED AT 250 WORDS)     

Stability of concentrated trimethoprim-sulfamethoxazole admixtures

The stability of trimethoprim-sulfamethoxazole (TMP-SMX) at various concentrations in 5% dextrose injection or 0.9% sodium chloride injection was studied. Appropriate volumes of TMP-SMX formulation (80 mg TMP and 400 mg SMX/5 mL) were mixed with 5% dextrose injection or 0.9% sodium chloride injection to provide dilutions of 1:25 v/v, 1:20 v/v, 1:15 v/v, and 1:10 v/v. Aliquots were removed at 0, 0.5, 1, 2, 4, 8, 14, 24, and 48 hours and filtered. The pH of the samples was determined, and the samples were assayed for trimethoprim and sulfamethoxazole content by high-performance liquid chromatography. Admixtures were visually inspected for precipitate before each sample was removed. The concentration of SMX in all admixtures did not change during the study period. The stability of TMP was dependent on concentration and vehicle. At a 1:25 v/v dilution, TMP was stable for 48 hours in 5% dextrose injection and 0.9% sodium chloride injection. At a 1:20 v/v dilution, TMP was stable for 24 hours in 5% dextrose injection and 14 hours in 0.9% sodium chloride injection. At a 1:15 v/v dilution, TMP was stable for four hours in 5% dextrose injection and two hours in 0.9% sodium chloride injection. At a 1:10 v/v dilution, TMP was stable for one hour in 5% dextrose injection and 0.9% sodium chloride injection. Concentrated solutions of TMP-SMX should be prepared in 5% dextrose injection, infused within one hour of preparation, and visually inspected for precipitation before and during infusion.     

注射用头孢唑肟钠与炎琥宁配伍稳定性考察

目的：考察注射用头孢唑肟钠与炎琥宁配伍的稳定性。方法：在25℃下,观察配伍液在8h内的外观、pH值变化,并用紫外分光光度法测定其含量变化。结果：两药在氯化钠注射液（9、0mg／mL）中配伍8h内各项变化均无显著性。结论：注射用头孢唑肟钠与炎琥宁在氯化钠注射液（9、0mg／mL）中配伍在室温下8h内基本稳定。     

Stability and sorption of FK 506 in 5% dextrose injection and 0.9% sodium chloride injection in glass, polyvinyl chloride, and polyolefin containers.

The effects of the diluent, the storage container, light, and infusion through various types of tubing on the stability and sorption of FK 506 were studied. Solutions of FK 506 in 0.9% sodium chloride injection or 5% dextrose injection were stored at room temperature (24 +/- 2 degrees C) in glass i.v. bottles, polyvinyl chloride (PVC) minibags, and polyolefin containers. FK 506 solution in 0.9% sodium chloride injection was stored in plastic syringes at room temperature and either exposed to normal room light or stored in the dark. FK 506 solution in 5% dextrose injection was placed in plastic syringes and infused through PVC anesthesia extension tubing, PVC i.v. administration set tubing, and fat emulsion tubing over a two-hour period. The infused samples and samples collected from the containers and syringes at intervals up to 48 hours were analyzed for FK 506 concentration by high-performance liquid chromatography. FK 506 concentrations remained greater than 90% of initial concentration for admixtures in 5% dextrose injection stored in glass bottles for 48 hours and for admixtures in 5% dextrose injection or 0.9% sodium chloride injection stored in polyolefin containers for 48 hours. No change in concentration was measured for admixtures in 0.9% sodium chloride injection stored in plastic syringes, and exposure to light did not affect the stability of FK 506 solution. No substantial change in concentration occurred in FK 506 solution in 5% dextrose injection infused through PVC anesthesia extension tubing, PVC i.v. administration set tubing, or fat emulsion tubing. FK 506 admixtures prepared with 5% dextrose injection or 0.9% sodium chloride injection should be stored in polyolefin containers. If polyolefin containers are not available, solutions should be prepared with 5% dextrose injection and stored in glass bottles.     

Stability of zidovudine in 5% dextrose injection and 0.9% sodium chloride injection

The stability of zidovudine at a concentration of 4 mg/mL in 5% dextrose injection and 0.9% sodium chloride injection in polyvinyl chloride infusion bags stored at room and refrigerated temperatures for up to eight days was studied. Zidovudine was diluted in 5% dextrose injection and in 0.9% sodium chloride injection to a concentration of 4 mg/mL. Six admixtures were prepared with each diluent; three were stored at room temperature (25 +/- 1 degree C) and three were refrigerated (4 +/- 1 degree C). At 0, 3, 6, 24, 48, 72, and 192 hours, 2-mL aliquots were removed. One milliliter of each aliquot was diluted to a zidovudine concentration of approximately 40 micrograms/mL and assayed in duplicate by a stability-indicating high-performance liquid chromatographic method. Visual inspection was performed at each sampling time for precipitation, turbidity, color change, and gas formation. Sample pH was recorded at 0 and 192 hours. In all admixtures, more than 97% of the initial zidovudine concentration remained throughout the study period. No visual or pH changes were observed. Zidovudine 4 mg/mL in admixtures with 5% dextrose injection or 0.9% sodium chloride injection stored in polyvinyl chloride infusion bags was stable for up to 192 hours (eight days) at room temperature and under refrigeration.     

Stability of cisplatin, iproplatin, carboplatin, and tetraplatin in commonly used intravenous solutions

The stability of cisplatin, iproplatin, carboplatin, and tetraplatin in common intravenous solutions was studied. Admixtures of each drug in each of the following vehicles were prepared in glass containers: 0.9% sodium chloride injection, 5% dextrose injection, 5% dextrose and 0.9% sodium chloride injection, 5% dextrose and 0.45% sodium chloride injection (admixtures were prepared in plastic bags also), and 5% dextrose and 0.225% sodium chloride injection. Drug concentrations were monitored for 24 hours using stability-indicating high-performance liquid chromatographic methods. The stability of cisplatin and tetraplatin was related to the chloride ion content of the infusion fluid; when the infusion fluid contained 0.9% sodium chloride, each of these drugs was present at greater than 90% of the original concentration after six hours. The stability of iproplatin was not related to chloride concentration. A slight increase in the decomposition rate of carboplatin was observed in the presence of chloride ion. Carboplatin and iproplatin are stable for 24 hours in all the infusion fluids studied, but carboplatin should not be diluted with solutions containing chloride ions because of possible conversion to cisplatin. Cisplatin is stable for 24 hours in admixtures containing sodium chloride concentrations of 0.3% or greater. Tetraplatin is stable for six hours in admixtures containing sodium chloride concentrations of at least 0.018%.     

Stability of pentamidine isethionate in 5% dextrose and 0.9% sodium chloride injections

The stability of pentamidine isethionate in small-volume intravenous admixtures was studied. In an initial experiment, duplicate admixtures containing pentamidine 1 or 2 mg/mL were prepared using 100 mL each of 5% dextrose injection and 0.9% sodium chloride injection in polyvinyl chloride (PVC) bags. All solutions were kept at room temperature and were assayed at various times up to 48 hours by high-performance liquid chromatography. Solutions were also examined visually and tested for pH at each assay time. In a second experiment, single admixtures containing pentamidine 2 mg/mL were prepared in 100-mL PVC bags of both 5% dextrose injection and 0.9% sodium chloride injection. After time-zero determinations of pentamidine concentration, pH, and visual clarity, solutions were allowed to run through PVC infusion sets at 20 mL/hr. Samples were collected at the distal end of each set at various times up to five hours for analysis of pentamidine concentration, pH, and clarity. All admixtures in the initial experiment retained greater than 90% of initial concentration for the 48-hour study period. However, 5% dextrose admixtures infused through PVC administration sets showed a loss in initial concentration of about 2%, while 0.9% sodium chloride admixtures lost about 10% of initial concentration after infusion through these sets. The pH of all solutions in both experiments varied by less than 0.5 units, and no particulate matter or color change was noted in any of the admixtures. In the concentrations and diluents studied, pentamidine appears to be stable for 48 hours in PVC bags. Slight losses in the initial concentrations of these solutions after infusing them through PVC infusion sets may be caused by adsorption to the set.