Brief Answer:
it is not at all possible, you can try with some other laboratory

Detailed Answer:
Hello,

Thanks for writing to us.

Clonazepam is long acting benzodiazepine. It is almost excreted in urine. If you are taking it regularly its half-life reaches almost up to 30 hours. In that case it must be detectable through urine screening test.
I have checked interactions of all the drugs you are taking with clonazepam and there is no single significant interaction found which can alter clonazepam level.
In general reasons for false negative results are:
- Dilute urine (excess fluid intake, diuretic use in excess)
- Infrequent drug use
- Prolonged time since last use
- Recent ingestion
- Insufficient quantity ingested
- Metabolic factors
- Inappropriate test used
- Elevated urine lactate

So likely possibility is that test result is false negative and that is mostly due to something wrong in testing method.

Let me know what did you eat in 24 hours before testing as well as since when are you taking clonazepam?

You can try on your own with readymade drug screening kit to detect benzodiazepine in urine or consult some other lab.

Hope I have answered your query, I will be happy to help further.

Regards,

Dr.Chintan Solanki.

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