Flecainide is a potent anti-arrhythmia agent, effective in a wide range of ventricular and atrial arrhythmias and tachycardias. Paradoxically, however, in myocardial infarct patients with either symptomatic or asymptomatic arrhythmia, flecainide exacerbates the arrhythmia and is not recommended for use in these patients.

(±)-Fluazifop-[d3] is a labelled analogue of Fluazifop, a grass-selective herbicide which inhibits acetyl-CoA carboxylase in sensitive plant species.

(±)-Fluoxetine-[d5] Oxalate is the labelled analogue of (±)-Fluoxetine Oxalate, which is a 5-HTP reuptake inhibitor and could be used as an antidepressant agent.