Selegiline, also known as L-deprenyl, is a substituted phenethylamine, a selective, irreversible inhibitor of Type B monoamine oxidase. Selegiline is available in pill form under many brand names (Eldepryl, Carbex, Atapryl) and is used to reduce symptoms in early-stage Parkinson's disease. Selegiline delays the time point when the L-DOPA (levodopa) treatment becomes necessary from about 11 months to about 18 months after diagnosis, which is beneficial despite not being definitive evidence of neuroprotection. The rationale for adding selegiline to levodopa is to decrease the required dose of levodopa and thus reduce the motor complications of levodopa therapy. Selegiline is also delivered via a transdermal patch (brand name, Emsam) and in this form, Selegiline is used as a treatment for the major depressive disorder. Selegiline (brand name Anipryl) is also used (at extremely high dosages relative to humans) in veterinary medicine to treat the symptoms of Cushing's disease and cognitive dysfunction (Canine Cognitive Dysfunction) in dogs. Side effects of the pill form include, in decreasing order of frequency, nausea, hallucinations, confusion, depression, loss of balance, insomnia, increased involuntary movements, agitation, arrhythmia, slow heart rate, delusions, hypertension, new or increased angina pectoris, and syncope. The main side effects of the patch form for depression included application site reactions, insomnia, diarrhea, and sore throat.

Phenylacetic acid (abr. PAA and synonyms are: α-toluic acid, benzeneacetic acid, alpha tolylic acid, 2-phenylacetic acid, β-phenylacetic acid) is an organic compound containing a phenyl functional group and acarboxylic acid functional group. Because it is used in the illicit production of phenylacetone (used in the manufacture of substituted amphetamines), it is subject to controls in countries including the United States and China Phenylacetic acid is used in some perfumes, possessing a honey-like odor in low concentrations, and is also used in penicillin G production. It is also employed to treat type II hyperammonemia to help reduce the amounts of ammonia in a patient's bloodstream by forming phenylacetyl-CoA, which then reacts with nitrogen-rich glutamine to form phenylacetylglutamine. This compound is then secreted by the patient's body. In Phase 2 of clinical research it investigated in the treatment of Brain and Central Nervous System Tumors.

Amphetamine is a potent central nervous system (CNS) stimulant that is used in the treatment of attention deficit hyperactivity disorder (ADHD), narcolepsy, and obesity. Amphetamine was discovered in 1887 and exists as two enantiomers: levoamphetamine and dextroamphetamine. The mode of therapeutic action in ADHD is not known. Amphetamines are thought to block the reuptake of norepinephrine and dopamine into the presynaptic neuron and increase the release of these monoamines into the extraneuronal space. At higher dosages, they cause release of dopamine from the mesocorticolimbic system and the nigrostriatal dopamine systems. Amphetamine may also act as a direct agonist on central 5-HT receptors and may inhibit monoamine oxidase (MAO). In the periphery, amphetamines are believed to cause the release of noradrenaline by acting on the adrenergic nerve terminals and alpha- and beta-receptors. Modulation of serotonergic pathways may contribute to the calming affect. The drug interacts with VMAT enzymes to enhance release of DA and 5-HT from vesicles. It may also directly cause the reversal of DAT and SERT. Several currently prescribed amphetamine formulations contain both enantiomers, including Adderall, Dyanavel XR, and Evekeo, the last of which is racemic amphetamine sulfate. Amphetamine is also prescribed in enantiopure and prodrug form as dextroamphetamine and lisdexamfetamine respectively. Lisdexamfetamine is structurally different from amphetamine, and is inactive until it metabolizes into dextroamphetamine.

Benzoic acid is a natural ingredient occurring in many foodstuffs and in plant extracts. Benzoic acid, its salts and esters are used as preservatives in cosmetic products, with a maximum concentration of 0.5 %. Benzoic acid and sodium benzoate are on the FDA list of substances that are generally recognized as safe (GRAS). Both may be used as antimicrobial agents, flavouring agents and as adjuvants with a current maximum level of 0.1% in food. Benzoic acid is a constituent of Whitfield Ointment, which is used for the treatment of fungal skin diseases such as tinea, ringworm, and athlete's foot. Adverse effect of Whitfield Ointment: occasionally, a localized mild inflammatory response occurs.

Formetorex was studied as an anorexic agent that has never been marketed. Information about the current use of this compound is not available.