US Pharm. 2012;37(9):46-47.
Method of Preparation: Calculate the quantity of each ingredient for the amount to be prepared. Accurately weigh or measure each ingredient. Pulverize the losartan tablets to a fine powder and mix the powder with the purified water. Geometrically, incorporate the Ora-Plus into the mixture, and mix well. Add the Ora-Sweet SF in increments to final volume, and mix well. Package and label.
Use: Losartan is used in the treatment of hypertension and the treatment of diabetic nephropathy in patients with type 2 diabetes mellitus and a history of hypertension; it also is used for stroke risk reduction in patients with hypertension and left ventricular hypertrophy.
Packaging: Package in tight, light-resistant polyethylene terephthalate (PET) containers.
Labeling: Shake well before taking. Keep out of the reach of children. Store in a refrigerator. Discard after 28 days.
Stability: A beyond-use date of up to 28 days when stored in a refrigerator may be used for this preparation.1,2
Quality Control: Quality-control assessment can include weight/volume, pH, specific gravity, active drug assay, color, rheologic properties/pourability, physical observation, and physical stability (discoloration, foreign materials, gas formation, mold growth).3
Discussion: Losartan potassium (Cozaar, C22H22ClKN6O, MW 461.00), a nonpeptide tetrazole derivative, is an angiotensin II receptor (type AT1) antagonist. It occurs as a white to off-white powder that is freely soluble in water and soluble in alcohols. The commercial product available (losartan potassium tablets) contains not less than 95.0% and not more than 105.0% of the labeled amount of losartan potassium. In children aged 6 to 16 years, the dosage of losartan potassium is 0.7 mg/kg once daily, to a maximum of 50 mg/day. Although food may actually decrease the rate of absorption of the drug and the peak concentrations achieved, the magnitude of the effect is not clinically important. Therefore, the drug may be given without regard to meals. In addition to losartan potassium, the 25-mg, 50-mg, and 100-mg tablets also contain microcrystalline cellulose, lactose hydrous, pregelatinized starch, magnesium stearate, hydroxypropyl cellulose, hypromellose, and titanium dioxide. The tablets may also contain carnauba wax.1
The term “water” is used to describe potable water from a public water supply that is suitable for drinking and is the beginning point of the official waters. It is a clear, colorless, odorless, and tasteless liquid. Purified water is water that is obtained by distillation, ion exchange, reverse osmosis, or some other suitable process. Water has a specific gravity of 0.9971 at room temperature, a melting point of 0°C, and a boiling point of 100°C. It is miscible with most polar solvents, and it is chemically stable in all physical states (ice, liquid, and steam).4
Ora-Plus is an oral suspending vehicle that accepts dilution of up to 50% or more with water, flavoring agents, or syrups and still retains its suspending properties. It has a pH of approximately 4.2 and an osmolality of about 230 mOsm/kg. Ora-Plus is a thixotropic vehicle with a viscosity of approximately 1,000 cps at 25°C. It 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.5
Ora-Sweet SF sugar-free syrup vehicle is a flavoring vehicle for oral extemporaneous preparations. It is a sugar-free, alcohol-free syrup flavored with a citrus-berry flavor blend. Ora-Sweet SF is buffered to a pH of approximately 4.2 and may be used alone or in combination with other vehicles. Ora-Sweet SF will tolerate a dilution to 50% with dissolved actives in water or suspending agents and still retain an acceptable taste. It has an osmolality of 2,150 mOsm/kg. Ora-Sweet SF contains water, sodium saccharin, xanthan gum, glycerin, sorbitol, citric acid, and sodium citrate as buffers; methylparaben, propylparaben, and potassium sorbate as preservatives; and flavoring agents.6
REFERENCES
1. U.S. Pharmacopeia 35/National Formulary 30. Rockville, MD: U.S. Pharmacopeial Convention, Inc; 2012:344-350,350-386,1126,3722-3724.
2. Lacy CF, Armstrong LL, Goldman MP, Lance LL. Drug Information Handbook. 13th ed. Hudson, OH: Lexi-Comp; 2005:914-916.
3. Allen LV Jr. Standard operating procedure for performing physical quality assessment of oral and topical liquids. IJPC. 1999;3:146-147.
4. Dubash D, Shah U. Water. In: Raymond CR, Sheskey PJ, Cook WG, Fenton ME, eds. Handbook of Pharmaceutical Excipients. 7th ed. Philadelphia, PA: Pharmaceutical Press; 2012:880-884.
5. Ora-Plus product information. Minneapolis, MN: Paddock Laboratories, Inc; 2010.
6. Ora-Sweet SF product information. Minneapolis, MN: Paddock Laboratories, Inc; 2010.
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