NaCl in the formulation of injections

[sharifhs]

During my industrial training I noticed many small volume of IM or IV injections (e.g., ketorolac inj, tiemonium inj etc.) were manufacturing with sodium chloride, I didn’t question them what the rationale behind though. I assumed it might be to produce isotonicity with body tissues. I’m wondering whether it is the only point because I suppose 1 or 2 ml of injection will not affect the total body tissues’ osmolarity if isotonicity is not maintained. Do you think any other principle works incorporating NaCl in the manufacture of injections? Thank you

[sharifhs]

someone told me NaCl is added in the manufacture of injection to minimize the sensation of pain..,

[johannes]

Might be due to stability & compatibility reasons?

[sharifhs]

Thank you Johannes. I'm giving the manufacturing formula of ketorolac (30mg/1ml) injection:

1. ketorolac tromethamine usp
2. Sodium metabisulfite bp (preservative)
3. Propylene glycol bp (solubilizer, for drugs with poor aqueous solubility)
4. Sodium chloride bp
5. Disodium edetate bp (preservative and antioxidant)
6. Sodium hydroxide bp (to adjust PH)
7. Water for inj bp

Any other suggestion?

[sharifhs]

It's a long time since I first posted this topic. Actually the compounds that contribute in the isotonicity of a product reduce the pain of injection in the areas with nerve ending. NaCl is usually used as a tonicity contributor when buffers alone fail to serve this function