The sulfa drugs are acetylated, primarily in the liver. The product is devoid of antimicrobial activity but retains the toxic potential to precipitate at neutral or acidic pH. This causes crystalluria and, therefore, potential damage to the kidney.

How does sulfonamide cause Crystalluria?

Especially sulfonamides are known to be little solubles in acidic urine. Among these drugs, sulfadiazine produces the so-called shocks of wheat crystals, whose formation can be avoided by opportune hydration and alkalinization of the patient.

What drugs cause Crystalluria?

In addition, crystalluria can be due to drugs such as sulphadiazine, acyclovir, triamterene, piridoxylate, primidone, which under the influence of various factors can crystallize within the tubular lumina and cause renal damage.