The sterifilt is the world's first purpose made single-use filter for illicit drugs. The polypropelene membrane filters particles but retains virtually no drug. In addition, it loses strength when wet, making re-use difficult.
The sterifilt is available in the UK from Exchange Supplies.
The sterifilt has a polypropylene membrane that filters much more effectively than makeshift filters (such as cigarette filters) and is much less likely to be shared because it:
retains far less drug than a makeshift filter
loses its strength when wet, so will break if re-use is attempted
This means that the sterifilt has significant potential to reduce the soft tissue infections and other problems arising from the re-use of dirty filters.
Filters that have been contaminated with blood may also a hepatitis C infection risk, although this is much less than from shared syringes providing filters reinforces the importance of not sharing.