There are various drugs and chemical substances that affect urine. Some change the color and/or smell of urine, while others interfere with the chemical reactions of the test strips, making the analysis useless.
In order to be able to make well-founded statements about the evaluation of the result, a drug history of the patient should always be made.
In the following table, schematically, some drugs or chemical substances that may have an influence on the urine sample are listed. The list is only an excerpt and has no claim to completeness.
| Interfering substance 7 factor | Influenced parameter |
| Amitriptyline | Urine color (green) |
| Beta-carotene | Urine color (yellow) |
| Betanin (Randen) | Urine color (red) |
| Captopril | Ketone (up), leukocytes (up), leukocytes (down) |
| Cefoxitin | leukocytes (up), urobilinogen (down), protein (up) |
| Cephalexin | Leukocytes (up) |
| Chemotherapy | Nitrite (down) |
| Quinidine | Protein (up) |
| Quinine | Urine color (yellow-brown) |
| Chlorhexidine | Protein (up) |
| Chloroquine | Protein (up) |
| Clavulanic acid | Leukocytes (up) |
| Curcumin | leukocytes (up), ketone (up), protein (up) |
| Deferoxamine | Urine color (red-brown) |
| Diurese / Diuretics | Specific weight (down), nitrite (down) |
| Gentamycin sulfate | Leukocytes (down) |
| Imipenem | Leukocytes (up), ketone (up), bilirubin (up) |
| Indometacin | Urine color (green) |
| Isoniazid | Urine color (orange) |
| Preservation – Boric Acid | Leukocytes (up) |
| Conservation – Formaldehyde | Leukocytes (up), Urobilinogen (down), Ketone (up) |
| Preservation – Formalin | Blood (down) |
| Long standing of the sample | Nitrite (down) (up), Urobilinogen (down), Bilirubin (down) |
| Levodopa | Urine color (red, black) |
| Meropenem | Leukocytes (up) |
| Methylene blue | Urine color (blue) |
| Metronidazole | Urine color (black) |
| Mitoxantrone | Urine color (green, blue) |
| Multivitamin preparations | Urine color (green, yellow) |
| N-acetylcysteine | Leukocytes (up), urobilinogen (down) |
| Sodium azide | Leukocytes (up) |
| Nitrite | Urobilinogen (down) |
| Nitrofurantoin | urine colour (yellow-brown); leukocytes (up), protein (up), glucose (down) |
| p-aminosalicylic acid | Protein (up), Urobilinogen (up), Bilirubin (up) |
| Penicillin | Bilirubin (up) |
| Phenazopyridine | Nitrite urine color (orange red) (up), urobilinogen (up), bilirubin (up), blood (up) |
| Phenolphtalein | Urine color (yellow-brown) |
| Phenylketone | Ketone (up) |
| Phenytoin | Urine color (brown-red) |
| Phthalein compounds | Ketone (up) |
| Polyvinylpyrrolidone | Protein (up) |
| Mercury salts | Leukocytes (up) |
| Cleaning agents (oxidizing) | Blood (up) |
| Rifampicin | Urine color (red) |
| Hydrochloric acid | Leukocytes (up), Bilirubin (up) |
| Sulfamethoxazole | Urine color (brown-red), urobilinogen (up) |
| Sulfonamide (trimethoprim) | Nitrite (down) |
| Tetracycline | Leukocytes (up) |
| Thiol Groups | Ketone (up), nitrite (down), glucose (up), bilirubin (down), blood (down) |
| Triamteren | Urine color (blue) |
