Ss. Tous et al., INTERACTIONS AND AVAILABILITY OF NITROFURANTOIN IN THE PRESENCE OF SOME NONSTEROIDAL ANTIINFLAMMATORY DRUGS, STP pharma sciences, 5(6), 1995, pp. 468-475
The interactions of the non-steroidal anti-inflammatory drugs viz ibup
rofen, flurbiprofen, ketoprofen and diclofenac sodium with nitrofurant
oin are revealed and characterized in this study. The solubility of ni
trofurantoin increased in the presence of the four non-steroidal anti-
inflammatory drugs in the following rank order : flurbiprofen > ketopr
ofen > ibuprofen > diclofenac sodium. The solubility of nitrofurantoin
increased linearly with an increase in the concentrations of non-ster
oidal anti-inflammatory drugs and a rise in temperature. The thermodyn
amic parameters were calculated from the solubility data. The data obt
ained indicate a possible complex formation between nitrofurantoin and
each of flurbiprofen and ketoprofen. The non-steroidal anti-inflammat
ory dr-rigs used had no profound effect on the dissolution characteris
tics of nitrofurantoin. The apparent partition coefficient of nitrofur
antoin between octanol and aqueous pH 1.2 significantly increased in t
he presence of the tested non-steroidal anti-inflammatory drugs. Job's
method of continuous variation was used to calculate the stoichiometr
ic ratio of the complex. It was found that a 1/1 complex formed betwee
n nitrofurantoin and each of ibuprofen, flurbiprofen and ketoprofen. T
he presence of non-steroidal anti-inflammatory drugs per se showed mar
ked changes in the UV and IR absorption of nitrofurantoin. These chang
es may indicate a sort of molecular interaction between nitrofurantoin
and the four non-steroidal anti-inflammatory drugs. Nitrofurantoin pr
oduced a favourable antibacterial activity in the presence of flurbipr
ofen, ketoprofen, ibuprofen or diclofenac sodium.