Stability of Adderall in extemporaneously compounded oral liquids.

The short-term stability of Adderall in three extemporaneously compounded oral liquids was studied. Three suspensions of Adderall 1 mg/mL were prepared from commercially available 10-mg Adderall tablets with Ora-Sweet, Ora-Plus, and a 1:1 mixture of Ora-Sweet and Ora-Plus. Each suspension was stored in the dark in a stability chamber at 25 degrees C and 60% relative humidity for 30 days. The stability of the active drug (a mixture of levoamphetamine and dextroamphetamine salts) in each of the three vehicles was determined immediately after preparation and at 10, 20, and 30 days by using gas chromatography-mass spectrometry (GCMS). No significant changes in concentrations of either amphetamine isomer occurred during the 30-day study period. Visual inspection of samples revealed no changes in color or odor. Extemporaneously compounded liquid oral formulations of Adderall 1 mg/mL in Ora-Sweet, Ora-Plus, or a 1:1 mixture of Ora-Sweet and Ora-Plus were stable for at least 30 days at 25 degrees C and 60% relative humidity.     

Stability of ganciclovir in extemporaneously compounded oral liquids.

The stability of ganciclovir in extemporaneously prepared sugar-containing and sugar-free oral liquids was studied. The contents of 80 250-mg capsules of ganciclovir were combined with Ora-Sweet or Ora-Sweet SF (sugar free) (Paddock Laboratories) to produce 200 mL of suspension with a ganciclovir concentration of 100 mg/mL. Five 1-mL samples were analyzed immediately, and the rest of the suspension was poured into five 60-mL amber polyethylene terephthalate bottles and stored at 23-25 degrees C. Samples were removed and analyzed with stability-indicating high-performance liquid chromatography on days 15, 35, 60, 91, and 123. The suspensions retained at least 96% of the initial ganciclovir concentration for 123 days. The pH of the suspensions was initially 4.5 and remained unchanged throughout the study. There was no detectable change in color or odor and no visible microbial growth in any sample. Ganciclovir 100 mg/mL was stable for 123 days in sugar-containing and sugar-free oral liquids stored at 23-25 degrees C in amber polyethylene terephthalate bottles.     

Stability of dolasetron in two oral liquid vehicles.

The stability of dolasetron 10 mg/mL over 90 days when prepared as an oral liquid formulation from commercially available tablets in both strawberry syrup and a sugar-free vehicle was studied. A liquid suspension of dolasetron mesylate 10 mg/mL was prepared from commercially available dolasetron tablets, OraPlus, and Ora-Sweet or strawberry syrup. Six samples of each formulation were prepared and stored in amber plastic bottles. Three samples of each formulation were refrigerated (3-5 degrees C) and three were stored at room temperature (23-25 degrees C). A 1-mL sample was withdrawn from each of the 12 bottles immediately and after 7, 14, 30, 60, and 90 days. After further dilution to an expected concentration of 10 micrograms/mL with sample diluent, the solutions were assayed in duplicate using high-performance liquid chromatography. The samples were also inspected for color and odor changes, and the pH of each sample was determined. The stability-indicating capability of the dolasetron assay was determined by forced degradation of four separate 10-mg/mL samples exposed to direct sunlight for 90 days. There were no detectable changes in color, odor, or taste and no visible microbial growth in any sample. At least 98% of the initial dolasetron concentration remained throughout the 90-day study period for all samples. An extemporaneously compounded oral liquid preparation of dolasetron mesylate 10 mg/mL in a 1:1 mixture of Ora-Plus and strawberry syrup or Ora-Sweet was stable for at least 90 days when stored at 3-5 or 23-25 degrees C.     

Stability of 1% rifampin suspensions prepared in five syrups

The stability and microbiological activity (potency) of rifampin in 1% w/v suspensions prepared extemporaneously using five syrups was studied. The contents of four 300-mg rifampin capsules (Rifadin, Merrell Dow Pharmaceuticals Inc.) were crushed and placed in amber glass bottles. The rifampin powder was combined with 120 mL of each of the following syrups: Syrup, NF; two commercially available simple syrups (Humco Laboratories and Whiteworth, Inc.), wild cherry syrup (Eli Lilly and Company), and a fruit-flavored syrup (Syrpalta). The bottles were then stored at room temperature or under refrigeration for six weeks. Portions of each suspension were removed and assayed using high-performance liquid chromatography (HPLC) and a microbiological assay technique initially and after two, four, and six weeks of storage. No significant changes in rifampin concentrations were detected by either assay technique over the study period. However, an increase in the concentration of rifampin degradation products was detected by HPLC assay, especially between the fourth and sixth weeks. A 1% w/v suspension of rifampin prepared using Rifadin capsules and any of the five syrups studied is stable for four weeks at room temperature or under refrigeration.     

Stability of acetazolamide in suspension compounded from tablets

The stability of acetazolamide in an extemporaneous suspension compounded from tablets was studied. Acetazolamide 25-mg/mL suspension was prepared by levigating the comminuted 250-mg tablets with 70% sorbitol solution. The mixture was incorporated into a suspension vehicle containing magnesium aluminum silicate and carboxymethylcellulose sodium. Appropriate sweeteners, flavoring agents, preservatives, humectants, and pH adjusters were then added. The suspension was stored in amber glass bottles at 5, 22, 30, 40, and 50 degrees C. Samples were analyzed for the concentration of acetazolamide by stability-indicating high-performance liquid chromatography on days 3, 7, 11, 18, 24, 32, 42, 54, and 79. For batches stored at 5, 22, and 30 degrees C, the initial acetazolamide concentration was maintained during the entire 79 days of the study. However, the concentrations in the batches stored at 40 and 50 degrees C were below 90% of the initial value after 79 and 32 days, respectively. The Arrhenius plot was used to predict a shelf life of the suspension at room temperature of 371 days. Acetazolamide oral suspension 25 mg/mL was stable for at least 79 days at 5, 22, and 30 degrees C. The formulation should be maintained at pH 4-5 and stored in amber glass bottles.     

Stability of tiagabine in two oral liquid vehicles.

The stability of tiagabine hydrochloride in two extemporaneously prepared oral suspensions stored at 4 and 25 degrees C for three months was studied. Tiagabine is used for adjunctive therapy for the treatment of refractory partial seizures. It is currently available in a tablet dosage form, which cannot be used in young children who are unable to swallow and given doses in milligrams per kilogram of body weight. No stability data are available for tiagabine in any liquid dosage form. Five bottles contained tiagabine 1 mg/mL in 1% methylcellulose:Simple Syrup, NF (1:6), and another five bottles had tiagabine 1 mg/mL in Ora-Plus:Ora-Sweet (1:1). Three samples were collected from each bottle at 0, 7, 14, 28, 42, 56, 70, and 91 days and analyzed by a stability-indicating high-performance liquid chromatographic method (n = 15). At 4 degrees C, the mean concentration of tiagabine exceeded 95% of the original concentration for 91 days in both formulations. At 25 degrees C, the mean concentration of tiagabine exceeded 90% of the original concentration for 70 days in Ora-Plus:Ora-Sweet formulation and for 42 days in 1% methylcellulose:syrup formulation. No changes in pH or physical appearance were seen during this period. The stability data for two formulations would provide flexibility for compounding tiagabine. Tiagabine hydrochloride 1 mg/,mL in extemporaneously prepared liquid dosage forms and stored in plastic bottles remained stable for up to three months at 4 degrees C and six weeks at 25 degrees C.     

Stability of propranolol hydrochloride suspension compounded from tablets

The stability of a propranolol hydrochloride suspension compounded from commercially available tablets was studied. Propranolol hydrochloride 10-mg tablets were triturated to a powder and incorporated into a commercially available suspension vehicle to yield a suspension with a theoretical propranolol hydrochloride concentration of 1 mg/mL. The suspension was divided into portions and stored in amber glass bottles at either room (25 degrees C) or refrigerated (2 degrees C) temperature for four months. The concentration of propranolol hydrochloride in the samples was determined by a stability-indicating, high-performance liquid chromatographic (HPLC) assay at 0, 30, 60, 90, and 120 days. Also at these times, the pH of the samples was measured, and the samples were inspected visually for evidence of microbial growth and ease of resuspension. The concentration of propranolol hydrochloride in the samples remained within 90% of the initial concentration throughout the study period. No important changes in the pH of the samples and no visible evidence of microbial growth were noted. This extemporaneous suspension of propranolol hydrochloride compounded from commercially available tablets is stable for at least four months when stored at room or refrigerated temperature.     

Limitations of compounding diazepam suspensions from tablets.

The concentration of diazepam in two types of suspension vehicles, as prepared from 10-mg tablets was tested over a 14-day period. The suspensions (1 mg/ml) were stored at room temperature in amber glass bottles. In one suspension, consisting of eight triturated tablets, 4.0 ml ethanol, 24.0 ml propylene glycol, 20.0 ml Syrup, USP, and 32.0 ml chocolate syrup, 90% of the diazepam was dissolved. This suspension demonstrated consistently acceptable concentrations of diazepam. In the other suspension, consisting of triturated tablets and Syrup, USP, only 25% of the diazepam was dissolved, and less consistent, subpotent concentrations of diazepam were found. The variation of diazepam concentrations between the suspensions was unrelated to the chemical stability of the drug.     

Stability and viscosity of a flavored omeprazole oral suspension for pediatric use.

PURPOSE: The stability and viscosity of preparations of a commercially available, flavored, immediate-release powder for oral suspension (omeprazole-sodium bicarbonate) during refrigerator and room temperature storage were investigated. METHODS: Omeprazole-sodium bicarbonate 20-mg packets were suspended to initial omeprazole concentrations of 0.6 and 2 mg/mL, and omeprazole-sodium bicarbonate 40-mg packets were suspended to initial omeprazole concentrations of 1.2, 2, 3, and 4 mg/mL. Suspensions were stored at 4 degrees C in darkness (refrigerated) or 22-25 degrees C (room temperature) in light for one week. A third set of suspensions was stored refrigerated for one month. Omeprazole's stability was quantified after 0, 6, 12, 24, 48, and 168 hours in one-week samples and after 0, 7, 14, 21, and 28 days in one-month samples using high-pressure liquid chromatography. Viscosities of refrigerated suspensions were measured after 0, 1, and 7 days. RESULTS: Refrigerated suspensions retained >98% and >96% of their initial omeprazole concentrations after one week and one month, respectively. Stability of room temperature suspensions was concentration dependent. After one week, the 0.6- and 1.2-mg/mL suspensions retained 87.2% and 93.1% of their respective initial omeprazole concentrations, whereas the 2-, 3-, and 4-mg/mL suspensions retained >97% of their initial omeprazole concentrations. Suspension viscosities varied 10-fold over the concentrations studied, but all were within the viscosity ranges of other commercially available oral suspensions. Prolonged refrigeration did not increase the suspensions' viscosities. CONCLUSION: Omeprazole-sodium bicarbonate suspensions of 0.6-4 mg/mL omeprazole were stored at 4 degrees C in darkness for up to 28 days. The viscosities of refrigerated suspensions did not increase over 7 days. Except for the 0.6 mg/mL preparations, suspensions stored at room temperature in the light retained >90% of their initial omeprazole content after 7 days, despite turning yellow.     

Stability of an extemporaneously prepared alcohol-free phenobarbital suspension.

PURPOSE: The physical and chemical short-term stability of alcohol-free, oral suspensions of phenobarbital 10 mg/mL prepared from commercially available tablets in both a sugar and a sugar-free vehicle was assessed at room temperature. METHODS: Phenobarbital oral suspension 10 mg/mL was prepared by crushing 10 60-mg tablets of phenobarbital with a mortar and pestle. A small amount of Ora-Plus was added to the phenobarbital powder to sufficiently wet the particles. A 1:1 mixture of Ora-Plus and either Ora-Sweet or Ora-Sweet SF was combined with the phenobarbital powder to produce a final volume of 60 mL. Three identical samples of each of the two different formulations were prepared and stored at room temperature in 2-oz amber plastic bottles. Immediately after preparation and at 15, 30, 60, and 115 days, the samples were assayed in duplicate by stability-indicating high-performance liquid chromatography. The samples were tasted and inspected for color and odor changes. The percent of the initial concentration remaining at each study time for each phenobarbital suspension was determined. Stability was defined as the retention of at least 90% of the initial concentration. RESULTS: There were no detectable changes in color, odor, and taste and no visible microbial growth in any sample. At least 98% of the initial phenobarbital concentration remained throughout the 115-day study period in both preparations. CONCLUSION: An extemporaneously prepared alcohol-free suspension of phenobarbital 10 mg/mL in a 1:1 mixture of Ora-Plus and Ora-Sweet or Ora-Sweet SF was stable for at least 115 days when stored in 2-oz amber plastic bottles at room temperature.