Effect of sodium deoxycholate on the dissolution and absorption of copper-indomethacin and zinc-indomethacin

The effects of sodium deoxycholate on the dissolution of indomethacin metal complexes were investigated. At pH 7.2, the dissolution of copper-indomethacin was very slow, while the dissolution of zinc-indomethacin was higher but less than that of indomethacin. In the presence of 5 mg of sodium deoxycholate, the dissolution of copper-indomethacin and zinc-indomethacin was significantly enhanced. The absorption of zinc-indomethacin in the rat jejunum was low, but that of copper-indomethacin was high, as compared to indomethacin. The addition of 0.2% sodium deoxycholate significantly enhanced the jejunal absorption of zinc-indomethacin in the rat, but did not increase the absorption of copper-indomethacin. Results indicated that the in vivo absorption behavior of zinc-indomethacin was predictable by in vitro dissolution, but such correlation was not applicable to copper-indomethacin. The absorption of copper-indomethacin was similar to that of indomethacin, in spite of its poor dissolution.