Formulation in Pharmacy Practice   2nd Edition

PYRAZINAMIDE
 
 
Pyrazinamide is sparingly soluble in water.

Formula 1

Pyrazinamide suspension 100mg per mL
 
Pyrazinamide tablets  500mg 20   
*Methylcellulose 1% 50  mL
Parabens 0.1  %
Syrup to   100  mL
 
*This can be either 50mL of a 1% solution or 0.5g methylcellulose per 100mL of final mixture.
 
Expiry:  30 days
 
Stability:   60 days.  This preparation is chemically stable for 60 days but has not been tested under "in-use" conditions.
 
Storage:  Amber (glass or plastic) bottles in a refrigerator or room temperature (25°C).
 
Shake well before use
 

 
NOTES
  1. The above preparation made without methylcellulose is also chemically stable but insoluble
    drug may be more likely to settle out on storage.
  2. The published formulation did not contain parabens.  Inclusion is justified as other pyrazinamide suspensions containing parabens have been shown to be stable.2
  3. Pyrazinamide suspension should not be mixed with other oral liquids such as isoniazid
    or rifampicin.
Alternatives:
Pyrazinamide suspension, 10mg per mL, prepared from crushed tablets in a vehicle of Ora-Sweet and Ora-Plus 1:1, or Ora-Sweet SF and Ora-Plus 1:1, or cherry syrup is chemically stable for 60 days at 5°C or 25°C and protected from light.2

REFERENCES
  1. Nahata MC, Morosco RS, Peritore SP.  Stability of pyrazinamide in two suspensions. Am J Health-Syst Pharm 1995; 52: 1558-60. [PubMed Link]
  2. Allen LV, Erickson MA.  Stability of pyrazinamide, quinidine sulfate, rifampin, and tetracycline in extemporaneously compounded oral liquids. 
     Am J Health-Syst Pharm 1998; 55: 1804-1809.[PubMed Link]

 
Formulation in Pharmacy Practice
2nd Edition