The compatibility and stability of octreotide acetate in the presence of diamorphine hydrochloride in polypropylene syringes

The current evidence base for the feasibility of 48-hour continuous subcutaneous infusions (CSCIs): A systematically-structured review

Background

A continuous subcutaneous infusion (CSCI) is an effective method of multiple drug administration commonly encountered in end of life care when the oral route is compromised. At present, current practice is to limit syringe driver infusion time to a maximum of 24 hours as dictated by available chemical stability data. However, the ability to deliver prescribed medication by a CSCI over 48 hours may have numerous benefits in both patient care and health service resource utilisation.

Aim

To examine and present the current evidence base for the stability of 48-hour multiple-drug CSCIs in current clinical practice.

Design

A systematically-structured review following PRISMA guidelines.

Data sources

Three electronic databases and the grey literature were searched with no time limits. Empirical studies reporting data on the chemical stability of continuous subcutaneous infusions or solutions stored in polypropylene syringes were included.

Results

Twenty-one empirical studies were included in this review reporting chemical compatibility and stability of 32 discrete combinations of twenty-four drugs tested at a variety of different drug concentrations. The majority of combinations reported were assessed as being chemically compatible. The greatest risk of clinically significant chemical degradation was observed with midazolam. Only one study reported the microbiological stability of the solution examined.

Conclusions

There is currently limited evidence for the physical, chemical and microbiological stability of solutions for continuous subcutaneous infusion over a period of 48 hours. More stability data is required before the use of 48-hour CSCIs can be evaluated for use within clinical practice.

Stability of octreotide acetate decreases in a sodium bisulfate concentration-dependent manner: compatibility study with morphine and metoclopramide injections

Purpose

Sodium bisulfate is known to affect the stability of octreotide. However, the critical concentration of sodium bisulfate is not known. Therefore, we assessed the critical concentration of sodium bisulfate needed to preserve the stability of octreotide using actual drugs containing sodium bisulfate.

Methods

Although morphine and metoclopramide preparations are considered to be compatible with octreotide, some of their products are known to contain sodium bisulfate. Thus, octreotide was mixed with preparations of sodium bisulfate solutions at serial concentrations and morphine and metoclopramide preparations containing sodium bisulfate, and octreotide stability was then evaluated using high performance liquid chromatography.

Results

Octreotide concentrations decreased significantly at a sodium bisulfate concentration of 0.1 mg/mL or higher after 10 days when octreotide was mixed with sodium bisulfate solutions at various concentrations. A significant decrease in octreotide concentrations also occurred when it was mixed with morphine and metoclopramide preparations containing sodium bisulfate and stored for 10 days; however, slight decreases were observed in the mixture with both preparations and were within the clinically acceptable range for morphine preparations.

Conclusions

These results indicate that the residual rate of octreotide decreases with time in a sodium bisulfate concentration-dependent manner when octreotide was mixed with morphine or metoclopramide. However, this incompatibility may be clinically acceptable when the final sodium bisulfate concentration is lower than 0.1 mg/mL and the mixed solution is used within 7 days.

Compatibility and stability of dexamethasone sodium phosphate and ketamine hydrochloride subcutaneous infusions in polypropylene syringes

The stability of ketamine hydrochloride injection and dexamethasone sodium phosphate injection, when mixed and stored in polypropylene syringes, was studied. Formulations containing ketamine hydrochloride (50 mg or 600 mg) and dexamethasone sodium phosphate (1 mg) in 0.9% sodium chloride injection (to 14 ml) were prepared and stored at 4 degrees C, 23 degrees C, and 37 degrees C, under normal fluorescent light conditions, for 192 hours. The concentrations of the drugs were determined at 0, 2, 4, 8, 24, 48, 96, and 192 hours using a validated high-pressure liquid chromatography method. The pH, color, and visible particles of each solution were also assessed at each time point. All formulations tested maintained more than 98% of the initial concentrations of both drugs, and no degradation products were detected. The solutions remained clear and colorless and the pH varied within 0.05 units throughout 192 hours. The results indicate that, at the concentrations studied, combinations of ketamine hydrochloride and dexamethasone sodium phosphate in 0.9% sodium chloride injection were physically and chemically stable for at least 192 hours (8 days) when stored in polypropylene syringes.