Abstract:

Infections of patients from consumption of contaminated pharmaceutical products constituted major health risk problems. Medicinal products are liable to microbial intrusion during in-use application. The current study focused on repeated contamination with constant level of microbiological burden by two bacteria viz. Staphylococcus aureus and Pseudomonas aeruginosa were used as dose-response models for infection through two different routes of administration. Nine different forms of insulin vials were subjected to this type of simulation study at constant assumed level of contaminations, preservative efficacy test (PET) and dose potency. Multi-spot contamination imitation study showed that initial fast rise in contamination, followed shortly by longer but steeper slope which finally turned into higher rate of contamination during the few last doses of the unit dosage forms, where the volume of the product became increasingly and progressively very small. When the probability of infection curves was constructed, both S. aureus and P. aeruginosa showed same pattern, with notably higher risk from septicemia route of the latter rather than subcutaneous route of the former. The present simulation study showed that continuous use of the same contaminated syringe progressively increased the risk of infection, especially at final few doses (between 3^th and 10^th last doses depending on the dosage form sizes in the vials and the administration volumes) of the product. Small volume parenterals (SVP) are especially products at higher risk than the larger volume ones.

Key words: Insulin vials, Staphylococcus aureus, Pseudomonas aeruginosa, Multi-spot contamination, PET, Simulation study