Monograph
J01EE01 - Sulfamethoxazole and Trimethoprim |
Porphyrinogenic |
P |
Rationale
The combination contains a notoriously porphyrinogenic sulfonamide component, inducer of CYP 3A4. Several references warn against it. Trimetoprim is substrate for CYP 2C9 and 3A4. Inhibits CYP 2C8, 2C19, 2D6,3A4. Warned against in three references.
Chemical description
sulfamethoxazol: Sulfonamide excreted in urine in unchanged form (20%), in acetylated form (60%) and in glucuronidated form (15%). trimethoprim: Bacteriostatic antibiotic perorally used (150-200 mg x 2) in urinary tract infections. About 10-20 % is metabolized in the liver.About 50 % is excreted by the kidneys in unchanged form within 24 hours. Sulfonamides: Australian list: unsafe/attacks. EPI-list: unsafe. French list: avoid. South African list: avoid /use with extreme caution only. Steim,Tchudy 1970: unsafe. Moore, Hift 1997: unsafe. Kalman, Bonkowsky: known to exacerbate disease. Andersson: Precipitates attacks (N=4) Trimethoprim: Martindale: unsafe/acute attacks. Australian list: unsafe. South African list: use with extreme caution only.
IPNet drug reports
Uneventful use reported in 3 patients with acute porphyria.
Similar drugs
Tradenames
This list comprises raw data collected from different countries.
In some cases, a more comprehensive list of available drug packages is included.
Consequently, very similar terms may therefore appear multiple times.
Bold names are the searchable terms, while the gray names that follow are all mapped to the bolded term.
Note: The cleaning is done automatically by a proprietary algorithm, and it may produce errors.
We strive to improve it continuously.
© NAPOS 2025