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.

Morpholine salicylate is a derivative of salicylic acid. It is a non-steroidal anti-inflammatory drug and was marketed under a tradename Retarcyl, Dolical and Deposal.

Bezitramide was developed as an orally long-acting analgesic compound and was marketed under the brand name Burgodin. The overdose of this drug caused death that is why it was withdrawn from the market.

Dipyrone, also known as Metamizole (INN), is an ampyrone sulfonate analgesic, antispasmodic and antipyretic. It was withdrawn from US market in 1977 on the basis of reports of agranulocytosis. Depyrone is still used to treat severe and diffucult for relieving pains of different origin; headache, tooth-ache, pains in the joints, muscles, following traumas and operations, gall and kidney colics, neurites, neuralgias, traumatic cerebrasthenia; inflammation of upper respiratory ways of microbial or virus origin; chorea; febrile states. Mechanism of action of dipyrone is complex. It is believed that dipyrone exerts its action by inhibiting COX-3, and activates opioid and cannabioid systems either itself, or by products of its metabolic degradation.

Dipyrone, also known as Metamizole (INN), is an ampyrone sulfonate analgesic, antispasmodic and antipyretic. It was withdrawn from US market in 1977 on the basis of reports of agranulocytosis. Depyrone is still used to treat severe and diffucult for relieving pains of different origin; headache, tooth-ache, pains in the joints, muscles, following traumas and operations, gall and kidney colics, neurites, neuralgias, traumatic cerebrasthenia; inflammation of upper respiratory ways of microbial or virus origin; chorea; febrile states. Mechanism of action of dipyrone is complex. It is believed that dipyrone exerts its action by inhibiting COX-3, and activates opioid and cannabioid systems either itself, or by products of its metabolic degradation.