Advances with para-hydrogen induced polarization open up new fields of applications for portable low-field NMR. Here we report the possibility of tracing drugs down to the micromolar regime. We could selectively polarize nicotine quantities similar to those found in one cigarette. Also less than 1 mg of harmine, a drug used for treatment of Parkinson's disease, and morphine extracted from an ***** solution were detectable after polarization with para-hydrogen in single-scan ¹H-experiments. Moreover, we demonstrate the possibility to selectively enhance and detect the ¹H-signal of drug molecules with PHIP in proton rich standard solutions that would otherwise mask the ¹H NMR signal of the drug.