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
- The above preparation made without methylcellulose is also chemically stable but insoluble
drug may be more likely to settle out on storage.
- The published formulation did not contain parabens. Inclusion is justified as
other pyrazinamide suspensions containing parabens have been shown to be stable.2
- 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
- Nahata MC, Morosco RS, Peritore SP. Stability of pyrazinamide
in two suspensions. Am J Health-Syst Pharm 1995; 52: 1558-60.
[PubMed Link]
- 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]
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