The formulation and sterilization of a surgical lubricant gel based on carboxypolymethylene

Comparing the effectiveness and lubricity of a novel Shea lubricant to 2% lidocaine gel for digital rectal examination: a randomized non-inferiority trial

This study compared the level of lubricity and pain reduction of a novel shea lubricant to 2% lidocaine gel during digital rectal examination (DRE). Our research group performed a 9-week single-blind non-inferiority trial at the Ho Teaching Hospital involving 153 patients. The primary outcome measure was the mean pain difference during the procedure using a Visual Analogue Scale. 75 and 78 patients were randomized to the shea lubricant and 2% lidocaine gel groups respectively. The analysis considered the per-protocol population. The mean pain difference at endpoint was Δ - 0.01. The 95% lower confidence interval was a -0.595 difference in means, above the non-inferiority (NI) limit of - 0.720, thus establishing non-inferiority (Δ - 0.01, 95% CI - 0.59 to 0.57, NI - 0.72). With secondary outcome measures, perianal pruritus (p = 0.728), discomfort (p = 0.446), bowel urgency (p = 0.077) and urinary urgency (p = 0.841) were similar during the procedure. Shea lubricant had better lubricity and ease of use (p = 0.002). While the novel shea lubricant achieved similar level of pain reduction as obtained with 2% lidocaine gel, it had better ease of performance and lubricity.

Final Report on the Safety Assessment of Carbomers-934, -910, -934P, -940, -941, and -962

The Carbomers are synthetic, high molecular weight, nonlinear polymers of acrylic acid, cross-linked with a polyalkenyl polyether. The Carbomer polymers are used in cosmetics and emulsifying agents at concentrations up to 50%. Acute oral animal studies showed that Carbomers-910, -934, -934P, -940, and -941 have low toxicities when ingested. Rabbits showed minimal skin irritation and zero to moderate eye irritation when tested with Carbomers-910 and -934. Subchronic feeding of rats and dogs with Carbomer-934 in the diet resulted in lower than normal body weights, but no pathological changes were observed. Dogs chronically fed Carbomer-934P manifested gastrointestinal irritation and marked pigment deposition within Kupffer cells of the liver. Clinical studies with Carbomers showed that these polymers have low potential for skin irritation and sensitization at concentrations up to 100%. Carbomer-934 demonstrated low potential for phototoxicity and photo-contact allergenicity. On the basis of the available information presented and as qualified in the report, it is concluded that the Carbomers are safe as cosmetic ingredients.

Effect of steam sterilization on the rheology of polymer solutions

The effect of steam sterilization (dwell@121 degrees C) on the apparent viscosity of solutions of carbomer 940P, guar gum, hydroxyethylcellulose (HEC), and xanthan gum was studied. Guar gum and carbomer 940P could be steam sterilized for 30 min without any change in the apparent viscosity. Steam sterilization of HEC and xanthan gum resulted in a substantial decrease in the apparent viscosity and the desirable shear-thinning rheology. The addition of sodium chloride to either polymer prior to steam sterilization diminished the effect of sterilization on the rheology. The apparent viscosity of xanthan solutions was not significantly affected if the solution was made isotonic with sodium chloride (0.15 M). The addition of sodium chloride to xanthan gum after steam sterilization resulted in full recovery of the initial rheological properties. Carbomers, guar gum, and xanthan (in 0.15 M NaCI) are candidates for use in pharmaceutical solutions/suspensions that are subjected to steam sterilization.