Limitations: This safety classification applies only to preparations containing a combination of the two drugs tropicamide and phenylephrine. The same ATC code (S01FA56) can in some countries be used for different combinations of tropicamide and other drugs, which in theory may or may not be porphyrinogenic. Please refer to the classification and monograph of each individual substance.

Administered locally in the eye and systemic exposure is insignificant.

Tropicamide is a phenylpropylamide. Phenylephrine is a phenol derivative.

Tropicamid in combination with phenylephrine is used to obtain pre-operative mydriasis (dilation of the pupil). It is administered as an ophthalmic insert.

Very low concentrations of phenylephrine and tropicamide were found in eye chamber water, below 6 µg/ml and 3 µg/ml, respectively. Plasma levels of phenylephrine measured during 6 hours in healthy volunteers were not detectable (< 0.5 ng/ml) (SPC). Plasma levels of phenylephedrine were well below 1 µM and hepatic exposure is therefore insignificant.

In oral administration, phenylephrine is metabolized via monoamine oxidase and sulfotransferase and probably no CYP enzymes are involved. No data is found for the metabolism of tropicamide.