Acriflavine (ACF) is a topical antiseptic. The hydrochloride form is more irritating than the neutral form. It is derived from acridine. Commercial preparations are often mixtures with proflavine. Acriflavine was developed in 1912 by Paul Ehrlich, a German medical researcher, and was used during the First World War against sleeping sickness. ACF has known trypanocidal, antibacterial, and antiviral activities. Effects of ACF on cancer cells were first reported 50 years ago. By present time was demonstrated that ACF a drug, that binds directly to HIF-1 alpha and HIF-2 alpha and inhibits HIF-1 dimerization and transcriptional activity and thus has potent inhibitory effects on tumor growth and vascularization. Also Acriflavine in combination with 3,6-diaminoacridine (proflavine) could prove to be a potential antimalarial drug and its pharmacological action can be due to inhibition of gyrase activity. This is achieved through interaction of the ACF with the DNA substrate. This interaction may lead to conformation change in DNA unsuitable for binding of gyrase with DNA.

Arsphenamine (brand name Salvarsan), a drug contains arsenic, was used to treat syphilis, but then it was substituted by the more active and less toxic agent.

Bornelone (also known as Bornelon) is used as ultraviolet (UV) absorber, in order to protect include cosmetic products against the influence of ultraviolet light. Bornelone is not allowed as a UV filter in sunscreens in the Europe, as it was discovered, that in contact with the skin contact dermatitis could cause.

Picrotoxin is a toxin obtained from the seeds of the shrub Anamirta cocculus and used as a central nervous system stimulant, antidote, convulsant, and non-competitive antagonist at GABAA receptors. Picrotoxin has been used as a CNS stimulant and an antidote in poisoning by CNS depressants, especially barbiturates also used for the treatment of respiratory distress. Exposure to picrotoxin causes eye and skin irritation, respiratory and digestive tract irritation and CNS effects. Despite its potential toxicity to mammals in large enough doses, picrotoxin is also sometimes used as a performance enhancer in horses.