Safety of reusing disposable plastic insulin syringes

53 diabetic patients took part in a study to assess the safety of reusing plastic disposable syringes for insulin injection. Each patient used the same plastic syringe for 7 days. The syringe needles were changed when blunt. No patient developed signs of infection at the injection site. Bacteriological assessment of the used syringes and needles showed no contamination in any of the syringes, although one needle was contaminated. The effectiveness of bacteriostatic additives to insulin preparations was demonstrated. The presence of these additives renders safe the practice of a diabetic patient reusing a plastic disposable syringe over a 7-day period.