Suspensions and diluents for metronidazole and baclofen

Abstract

Suspensions of metronidazole or baclofen and/or salts or ester derivative thereof, such as metronidazole benzoate, are disclosed. The suspension my include metronidazole or baclofen, and/or a salt or ester derivative thereof a hydrocolloid stabilizer, simethicone emulsion, a buffer, such as sodium citrate, (dihydrate), a preservative, a thickening agent, a sweetener, and water.

What is claimed is: 
     
         1 . A liquid oral pharmaceutical composition of baclofen or a salt thereof, comprising:
 a) 5 mg/ml of baclofen or a salt thereof;   b) citric acid (anhydrous);   c) hydroxyethyl cellulose;   d) propylene glycol;   e) sodium benzoate; and;   f) water,   wherein a pH of the liquid oral pharmaceutical composition is between 3.0 and 6.0, and   wherein the liquid oral pharmaceutical composition retains less than +/−5% variation of baclofen concentration measured by a USP assay for at least 30 days when stored at room temperature.   
     
     
         2 . The pharmaceutical composition of  claim 1 , wherein the pharmaceutical composition retains less than +/−5% variation of baclofen concentration measured by a USP assay for at least 30 days when stored at 38-42° C. 
     
     
         3 . The pharmaceutical composition of  claim 1 , wherein the pharmaceutical composition retains less than +/−5% variation of baclofen concentration measured by a USP assay for at least 30 days when stored at 15-30° C. 
     
     
         4 . The pharmaceutical composition of  claim 1 , wherein the pharmaceutical composition retains less than +/−2% variation of baclofen concentration measured by a USP assay for at least 30 days when stored at room temperature. 
     
     
         5 . The pharmaceutical composition of  claim 1 , wherein the pH of the pharmaceutical composition is between 3.6 and 4.6. 
     
     
         6 . The pharmaceutical composition of  claim 1 , wherein the pH of the pharmaceutical composition is between 4.0 and 4.3. 
     
     
         7 . The pharmaceutical composition of  claim 1 , wherein the citric acid is present at 0.12-0.6% (w/v). 
     
     
         8 . The pharmaceutical composition of  claim 1 , wherein the citric acid is present at 0.12% (w/v). 
     
     
         9 . The pharmaceutical composition of  claim 1 , wherein the sodium benzoate is present at 0.1-0.2% (w/v). 
     
     
         10 . The pharmaceutical composition of  claim 1 , wherein the sodium benzoate is present at 0.1% (w/v). 
     
     
         11 . The pharmaceutical composition of  claim 1 , wherein the propylene glycol is present at 5% (w/v). 
     
     
         12 . The pharmaceutical composition of  claim 1 , wherein the hydroxyethyl cellulose is present at 0.5% (w/v). 
     
     
         13 . The pharmaceutical composition of  claim 1 , wherein the pharmaceutical composition further comprises simethicone. 
     
     
         14 . The pharmaceutical composition of  claim 13 , wherein the simethicone is a 30% simethicone emulsion and is present at 0.1500-0.250% (w/v). 
     
     
         15 . The pharmaceutical composition of  claim 1 , wherein the pharmaceutical composition further comprises a coloring agent, a flavoring agent, a sweetener, or a combination thereof. 
     
     
         16 . The pharmaceutical composition of  claim 15 , wherein the pharmaceutical composition comprises a sweetener. 
     
     
         17 . The pharmaceutical composition of  claim 16 , wherein the sweetener is one or more of ammonium glycyrrhizate, sucralose, and saccharin sodium. 
     
     
         18 . The pharmaceutical composition of  claim 17 , wherein the sweetener is sucralose and
 is present at 0.05-0.2% (w/v).   
     
     
         19 . The pharmaceutical composition of  claim 15 , wherein the pharmaceutical composition comprises a coloring agent and a flavoring agent. 
     
     
         20 . The pharmaceutical composition of  claim 1 , wherein the baclofen or a salt thereof is baclofen.