Mephobarbital us a barbiturate derivative used primary as an anticonvulsant, but also as a sedative and anxiolytic. Marketing of mephobarbital was discontinued in 2012.

Aconitine is an alkaloid found in the Aconitum species. Aconitine is a highly toxic cardiotoxin and neurotoxin. In China and other countries, the herbal extract containing aconitine was used for the treatment of pain in musculoskeletal disorders, however the safety margin between therapeutic analgesic effect of aconitine and its known cardiotoxic effect is so narrow that the treatment may cause poisoning and death. The mechanism of aconitine action is explained by its ability to activate voltage-dependent sodium-ion channels.

Sparteine is a class 1a antiarrhythmic agent; a sodium channel blocker. It is the predominant alkaloid in Lupinus mutabilis, and is thought to chelate the bivalents calcium and magnesium. It is not FDA approved for human use as an antiarrhythmic agent. It is also used as a chiral base in organic chemistry, and as a ligand in organic chemical synthesis. Marketed under the brand name Spal in Taiwan and Sparteine in Brazil.

QUININE HYPOPHOSPHITE, a salt of quinine, was formerly used, along with the hypophosphites of sodium, potassium, calcium, and iron, in the treatment of phthisis and neurasthenic conditions.

Melatonin (5-methoxy N-acetyltryptamine) is a hormone synthesized and released from the pineal gland at night, which acts on specific high affinity G-protein coupled receptors to regulate various aspects of physiology and behaviour, including circadian and seasonal responses, and some retinal, cardiovascular and immunological functions. Melatonin is also made synthetically and available without a prescription as an over-the-counter (OTC) dietary supplement in the U.S. Melatonin supplementation has many uses, however, it has been widely studied for treatment of jet lag and sleep disorders. Parents may consider using melatonin to help their child who has a trouble falling asleep. A medical professional should always evaluate insomnia or other sleeping disorders in children. Additionally, melatonin has been shown to protect against oxidative stress in various, highly divergent experimental systems. There are many reasons for its remarkable protective potential. In mammals, melatonin binds to a number of receptor subtypes including high-affinity (MT1 and MT2) and low-affinity (MT3, nuclear orphan receptors) binding sites, which are distributed throughout the central nervous system and periphery.

Aminophenazone is a phenyl-pyrazolone derivative with potent analgesic and antipyretic properties. Aminophenazone has been used as salt or complexes, including topically as the salicylate. It was recommended for the treatment of a fever, neuralgia, myositis, acute rheumatism, arthritis, chorea. In 1999 the FDA suspended aminophenazone. The drug caused agranulocytosis. Some of the cases of agranulocytosis were fatal. Another reason for suspending this drug from the market was its ability to react with nitrite-containing food, thus forming carcinogenic nitrosamines. A breath test with 13C-labeled aminopyrine has been used as a non-invasive measure of cytochrome P-450 metabolic activity in liver function tests.

Phenacetin was used as an analgesic and fever-reducing drug in both human and veterinary medicine for many years. Since a major portion of a dose of phenacetin is rapidly metabolised to paracetamol, it seems possible that phenacetin owes some of its therapeutic activity to its main metabolite, paracetamol, whereas its most troublesome side effect (methaemoglobinaemia) is due to another metabolite, p-phenetidine. Phenacetin was shown to inhibit cyclooxygenase (COX)-3, a cyclooxygenase-1 variant while p-phenetidine potently inhibits both COX-1 and COX-2. There is sufficient evidence in humans for the carcinogenicity of analgesic mixtures containing phenacetin. Analgesic mixtures containing phenacetin cause cancer of the renal pelvis, and of the ureter. Phenacetin was withdrawn from many analgesic mixtures long before the legal ban in several countries.

Quinine ascorbate is a salt of antimalarial drug quinine and ascorbic acid (vitamin C). Ascorbate reduces the potency of quinolone-containing anti-malarial drugs. Quinine ascorbate was marketed as a component of over-the-counter smoking deterrent products but was not recognized as safe by the FDA regulation in 1993.

Flotufolastat F 18 (POSLUMA®) is an 18F-labelled radiohybrid (rh) prostate-specific membrane antigen (PSMA)-targeted imaging agent being developed by Blue Earth Diagnostics, a subsidiary of Bracco Imaging, for prostate cancer imaging. In May 2023, flotufolastat F 18 received its first approval in the USA as a radioactive diagnostic agent for positron emission tomography (PET) of PSMA positive lesions in men with prostate cancer with suspected metastasis who are candidates for initial definitive therapy or with suspected recurrence based on elevated serum prostate-specific antigen (PSA) level. Flotufolastat F 18 binds to PSMA (IC50 = 4.4 nM) expressed on cells, including prostate cancer cells, and is internalized. Prostate cancer cells usually overexpress PSMA. Fluorine-18 is a beta emitting radionuclide that can be detected using positron emission tomography.

Berberine, an alkaloid isolated from Rhizoma Coptidis, is known to have a wide array of therapeutic effects including antimicrobial, antineoplastic, and hepatoprotective effects. It is found in several plants including European barberry, goldenseal, goldthread, Oregon grape, phellodendron, and tree tumeric. Berberine seems to slightly reduce blood sugar levels in people with diabetes. Berberine might lower blood pressure. Berberine is possibly safe for most adults for short-term use when taken by mouth or applied to the skin.