Tablets are midazolam maleate. Injection is midazolam hydrochloride.
The aqueous solubility of midazolam hydrochloride is pH dependent.
Solubility increases with decreasing pH and is between 10 - 20mg per mL at pH 3.
Midazolam hydrochloride is stable at pH 3 - 3.6. The injection (5mg per mL) has a pH of about 3.1
Formula A2
Midazolam 2.5mg per mL |
| |
| Midazolam hydrochloride injection, 5mg per mL |
10 |
mL |
| Syrup BP or NF |
to 20 |
mL |
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|
The final pH should be no more than 4.2, adjustment to a pH of about 3.5 ensures that the drug stays
in solution. |
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|
Expiry date/Stability: 30 days, if preserved. |
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Storage: Refrigerate. Also stable at room temperature. |
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NOTES
- Undiluted injection could be administered orally.
- If syrup is undesirable in the formulation, dilute the injection with sterile water and adjust the
pH to 3 - 3.5 if necessary.
- Syrup NF = 85g sucrose in 100mL of water.
REFERENCES
- McEvoy G.K., ed. American Hospital Formulary Services, Drug Information. Bethesda, MD: ASHP;
1993: 1423.
- Steedman S.L., Koonce J.R., Wynn J.E., Brahen N.H. Stability of midazolam hydrochloride in a flavoured dye-free oral solution. Am J Hosp Pharm 1992; 49: 615-8.
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