If MCS is suspected, step-by-step diagnostics makes sense in order to limit the costs. First of all, a test should be carried out to roughly differentiate whether a detoxification disorder is present in phase 1 and/or phase 2. This includes determining the activity of the important detoxification enzymes in phase 2 (total GST activity) and the caffeine test. The caffeine test is relatively simple. The patient takes a dose of caffeine according to his body weight and the caffeine level is determined after one hour and 5 hours. If phase 1 is disrupted, the result will be higher caffeine values because the caffeine could only be broken down with a delay. The delayed degradation between the 1 hour and the 5 hour value is then particularly noticeable.  Even symptoms such as dizziness, which occur after taking the caffeine, already give an indication of the detoxification disorder.

 

If phase 1 detoxification is unremarkable, phase 2 should be examined. The determination of the genes of the detoxification enzymes of the NAT, GST and CYP groups plays a role here.