Phenazepam

The lab found that there were actually traces of finazopam in Olga's system.

Now, the most likely reason that it wasn't picked up in Olga's system at the hospital is because Phenazepam is illegal in the United States.

Phenazepam is a long-acting benzodiazepine drug that was developed in the Soviet Union in the 1970s and is illegal in the US and most European countries.

but it is still used in Russia.

Just to sort of put it in perspective, the dose of finazepam that you would need for therapeutic purposes is one-tenth the dose of something like diazepam.