Medulla NSAIDs

The acidic nature and lipid solubility of these compounds are important. The lipid solubility of an NSAID determines its penetration into the central nervous system and hence the incidence of nervous system-related adverse effects and perhaps adverse skin reactions (9,10). The weak acid nature affects tissue distribution, which explains why NSAIDs have actions at certain sites (for example synovial tissue of inflamed joints) and also contribute to triggering particular adverse reactions at others (for example the stomach and renal medulla) (11). 

Aspirin and NSAID suppress prostaglandin production by inhibiting cyclooxygenase enzymes. Renal blood flow, particularly within the renal medulla, is highly dependent upon systemic and local production of vasodilatory prostaglandins. 

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