Possible Interaction: Indomethacin and Niacin

“When the same dose of nicotinic acid was given after pretreatment with indomethacin , the blood flow increase was only 1/3 of that without indomethacin.”

“OAT2-specific transport of NA was inhibited by ketoprofen and indomethacin (known OAT2 inhibitors) in a concentration-dependent manner.”

“Moreover, transdermal penetration of indomethacin and nicotinic acid amide was enhanced significantly.”

“In the rat stomach strips nicotinic acid (or Na-nicotinate) induces concentration-dependent contractions that are drastically antagonized by indomethacin but not by the other inhibitors tested (scopolamine, phenoxybenzamine, propranolol, methysergide, pyrilamine, imidazole, anacardic acid).”

“In isolated slices from guinea-pig ears, nicotinic acid increased the level of cyclic AMP; this effect was inhibited by indomethacin.”

“In preliminary solubility studies, it was found that there was more than fivefold enhancement in the aqueous solubility of indomethacin (poorly water-soluble drug) in 2 M niacinamide solution as compared to its aqueous solubility at 28 ± 1°C.”

“Along with 2-hydroxynicotinic acid (Ki = 2.3 × … following nonsteroidal anti-inflammatory compounds competed reversibly with nicotinic acid for the enzyme: flufenamic acid (Ki = 4.6 × 10−5M), mefenamic acid (Ki = 7.…), salicylic acid (Ki = 1.6 × 10−4M), phenylbutazone (Ki = 1.6 × 10−4M), and indomethacin (Ki = …−4M).”