Abstract
The abuse of codeine containing combination
analgesics leads to significant non-opioid toxicities. Cold water
extraction (CWE) reduces these side effects but can also provide
access to highly restricted codeine phosphate. This study aims to
assess the effectiveness of CWE for a range of drug combinations
available on the Australian market as ’pharmacist-only’
medicines. Six products containing codeine phosphate in
combination with paracetamol, ibuprofen or aspirin as well as an
excipient free mixture of codeine phosphate and ibuprofen
lysinate were treated by CWE and the resulting drug content in
the filtrate analysed by HPLC. The effect of an additional
acidification step was also assessed for combinations containing
aspirin and ibuprofen lysinate. It was found that CWE is able to
remove almost all ibuprofen (up to 97%), but significant amounts
of paracetamol (between 70% and 80% depending on the
formulation) and aspirin (nearly 60%) remain in the filtrate. An
additional acidification step can reduce the residual amount of
dissolved aspirin to about 42%. The substitution of ibuprofen
with ibuprofen lysinate allows the removal of the NSAID from
the filtrate (via CWE followed by acidification) but lysinate as a
water soluble impurity remains.
analgesics leads to significant non-opioid toxicities. Cold water
extraction (CWE) reduces these side effects but can also provide
access to highly restricted codeine phosphate. This study aims to
assess the effectiveness of CWE for a range of drug combinations
available on the Australian market as ’pharmacist-only’
medicines. Six products containing codeine phosphate in
combination with paracetamol, ibuprofen or aspirin as well as an
excipient free mixture of codeine phosphate and ibuprofen
lysinate were treated by CWE and the resulting drug content in
the filtrate analysed by HPLC. The effect of an additional
acidification step was also assessed for combinations containing
aspirin and ibuprofen lysinate. It was found that CWE is able to
remove almost all ibuprofen (up to 97%), but significant amounts
of paracetamol (between 70% and 80% depending on the
formulation) and aspirin (nearly 60%) remain in the filtrate. An
additional acidification step can reduce the residual amount of
dissolved aspirin to about 42%. The substitution of ibuprofen
with ibuprofen lysinate allows the removal of the NSAID from
the filtrate (via CWE followed by acidification) but lysinate as a
water soluble impurity remains.
| Original language | English |
|---|---|
| Pages (from-to) | 1-4 |
| Journal | Journal of Advances in Medical Research |
| Volume | 1 |
| Issue number | 4 |
| Publication status | Published - 2016 |