7-Methylxanthine is a methyl derivative of xanthine, found occasionally in human urine. 7-Methylxanthine is one of the purine components in urinary calculi. 7-methylxanthine (7-MX) is a metabolite of caffeine and theobromine, and has been shown to have low toxicity and no carcinogenic effects. 7-MX is known as a non-selective adenosine antagonist and has been shown to work against myopia. 7-MX has little effect on the proliferation or apoptosis of human RPE cells; however, 7-MX disturbs the proportion of cells in the G1 stage and inhibits the expression of ADORA1, ADORA2A, and ADORA2B in short-term treatment. 7-MX has been confirmed to reduce the severity of myopia and eye elongation induced by forming deprivation in guinea pigs and to counteract the thinning of the posterior sclera and of collagen fibrils induced by form deprivation. A clinical trial showed that 7-MX reduced eye elongation and myopia progression in childhood myopia.

5-Methoxytryptamine (aka 5-MT, mexamine) is a tryptamine derivative closely related to the neurotransmitters serotonin and melatonin. 5-MT is produced endogenously at low levels; it is biosynthesized by deacetylation of melatonin in the pineal gland. 5-MT acts as a full agonist at the 5-HT1, 5-HT2, 5-HT4, 5-HT6, and 5-HT7 receptors. It is often used as a chemical probe in the study of serotonin receptors, but it has also been used in a clinical trial to mitigate the anemic effects of cisplatin chemotherapy.

Hydromorphinol, an opioid, and is a derivative of morphine and possesses similar properties: sedation, analgesia, and respiratory depression. Hydromorphinol is under the control according to US Single Convention 1961.

Taleranol (also known as P-1560) a weak estrogen and a minor metabolite and epimer of the drug, zeranol. Zeranol is an anabolic agent that used in animal feed and is intended for human consumption, is noncarcinogenic, nonteratogenic, and nonmutagenic.

Carabestine is the active first-pass metabolite of Ebastine and acts as a histamine H1 receptor antagonist which has been investigated as a potential allergy medication. Ebastine is marketed under a number of brand names.

Ethypicone is a hypnotic and sedative agent.

Etiocholanone is an androstane neurosteroid. Etiocholanone potentiates GABA-A receptor currents and exerts anticolvunsant properties in rodents. Etiocholanolone demostrates pyrogenic properties.