Solubility problems with Guaifenesin

Composition I

codeine phosphate 400 mg Pseudo-EPHEDRINEHCL 1.2 g tripolidineHCl 80 mg Guaifenesin 4 G Ethanol 94 degree 5 G Vanillin 200 mg Sorbitol Syrup NF6 AD 200 ml

This composition gives rise to crystallization; when sorbitol syrup is replaced by a single syrup, one does not obtain crystallization. How can this syrup (preferably with sorbitol syrup, suitable for diabetics) be prepared? Through the professional association I got the proposal: Add 0.15% Nacitraat to avoid crystallization. This addition does not appear to prevent crystal formation.

Composition II

chloropheniraminemaleate 160 mg Codeinephosphate 400 mg Pseudo-Ephedrinehcl 500 mg Guaifenisine 6 G Vanille-Aroma 10 Dr Sugar syrup up to 200 ml

After a few days of crystallization.

Discussion Indeed in both cases, guiafenisine crystallizes out. The difference between sorbitol syrup and sugar syrup is peculiar. The solubility data for Guiafenisine are: 1 on 70 in water; 1 in 10 in alcohol; 1 in 15 in propylene glycol, 1 on 50 in glycerin and sugar syrup and 1 on 80 in sorbitol syrup.

In The case of the first composition, the sorbitol syrup dissolves approximately 3.25 g and in the alcohol 0.5 g being in the total 3.75 g guiafenisine. If sugar syrup is used, we already get 4 G dissolved in the syrup. So no crystallization. Therefore, by doubling the amount of alcohol in the first composition we get everything sorted out. In the case of the second composition, we replace 15 ml of sugar syrup with 15 ml of alcohol.