US Pharm. 2018;43(5):46-47.
Method of Preparation: Calculate the required quantity of each ingredient for the total amount to be prepared. Accurately weigh or measure each ingredient. Pulverize the required number of tablets to a fine powder, or use the powder. Add a small quantity of Ora-Plus to form a smooth paste. Geometrically, incorporate the remainder of the Ora-Plus and mix well. Add the Strawberry Syrup in portions to final volume, with thorough mixing after each addition. Package and label.
Use: Levofloxacin is a fluoroquinolone anti-infective agent. It is used in the treatment of respiratory tract infections, acute exacerbations of chronic bronchitis, community-acquired pneumonia, nosocomial pneumonia, skin and skin-structure infections, urinary tract infections and prostatitis, endocarditis, gastrointestinal-tract infections, anthrax, chlamydial infections, gonorrhea and associated infections, meningitis and central nervous system infections, mycobacterial infections, nongonococcal urethritis, pelvic inflammatory disease, plague, and ophthalmic infections.1,2
Packaging: Package in tight, light-resistant containers.
Labeling: Shake well before taking. Keep out of the reach of children.
Stability: A beyond-use date of up to 57 days when stored at either room temperature or refrigerated temperature may be used for this preparation.1,3 Study data showed no drug loss at either room temperature or refrigerated temperature after 57 days. There was no appreciable change in the pH over the same time period in any of the samples.
Quality Control: Quality-control assessment can include weight/volume, pH, specific gravity, active drug assay, physical observation (color), rheologic properties/pourability, and physical stability (discoloration, foreign materials, gas formation, mold growth).4
Discussion: Levaquin (levofloxacin) oral solution has been discontinued by the manufacturer, but generic formulations are available commercially. However, there may be an excipient in the generic formulations that the patient cannot tolerate, so the formula presented here may be suitable. With regard to the above formula, if a more acidic pH is desired, a 1% methylcellulose gel could be used in place of the Ora-Plus and an acidic syrup, such as cherry or orange, could be used instead of the Strawberry Syrup. However, in that case, the same beyond-use date could not be used; the date would be limited to 14 days at refrigerated temperature.
Levofloxacin (C18H20FN3O4.1/2 H2O, MW 370.38) is a synthetic broad-spectrum antibacterial agent for oral and IV administration. Levofloxacin is the levo isomer of ofloxacin. It occurs as a light yellowish-white to yellow-white crystal or crystalline powder. Levofloxacin exists as a zwitterion at the pH conditions in the small intestine. It is soluble approximately 100 mg/mL in the pH range of 0.6 to 5.8; above a pH of 6.7, the solubility decreases and reaches a minimum value of about 50 mg/mL at a pH of 6.9. Generic levofloxacin tablets may contain lactose, polydextrose, and polyethylene glycol. One generic levofloxacin oral solution contains the following inactive ingredients: artificial and natural flavors, ascorbic acid, benzyl alcohol, caramel color, glycerin, hydrochloric acid, propylene glycol, purified water, sucralose, and sucrose. It may also contain a solution of sodium hydroxide for pH adjustment. Another generic oral solution contains artificial bubble-gum flavor, artificial grape flavor, ascorbic acid, glycerin, hydrochloric acid, PFC Bitter Mask F-9885, propylene glycol, purified water, saccharin sodium, and sucrose, and sodium hydroxide may be used to adjust the pH.1,2,5,6
Ora-Plus is an oral suspending vehicle that accepts dilution of up to 50% or more with water, flavoring agents, or syrups while still retaining its suspending properties. Ora-Plus has a pH of approximately 4.2 and an osmolality of about 230 mOsm/kg. It is a thixotropic vehicle with a viscosity of approximately 1,000 cps at 25°C. Ora-Plus contains purified water, microcrystalline cellulose, sodium carboxymethylcellulose, xanthan gum, carrageenan, sodium phosphate, and citric acid as buffering agents; simethicone as an antifoaming agent; and potassium sorbate and methylparaben as preservatives.7
Strawberry Syrup is a commercial syrup sold by Lyons-Magnus of Fresno, California.8
REFERENCES
1. U.S. Pharmacopeia/National Formulary [current revision]. Rockville, MD: U.S. Pharmacopeial Convention, Inc; April 2018.
2. McEvoy GK, ed. AHFS Drug Information 2016. Bethesda, MD: American Society of Health-System Pharmacists; 2016:364-373.
3. VandenBussche HL, Johnson CE, Fontana EM, Meram JM. Stability of levofloxacin in an extemporaneously compounded oral liquid. Am J Health Syst Pharm. 1999;56:2316-2318.
4. Allen LV Jr. Standard operating procedure for performing physical quality assessment of oral and topical liquids. IJPC. 1999;3:146-147.
5. Drugs.com. Levofloxacin. www.drugs.com/pro/levofloxacin.html. Accessed April 6, 2018.
6. RxList. Levaquin. www.rxlist.com/levaquin-drug.htm. Accessed April 6, 2018.
7. Ora-Plus product information. Allegan, MI: Perrigo; 2018.
8. Lyons Magnus. www.lyonsmagnus.com. Accessed April 5, 2018.
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