What are the properties and effects of Phenacetin?

Phenacetin, chemical formula C10H13NO2, is usually combined with aspirin and caffeine to form a less toxic compound aspirin for the treatment of the common cold. What follows is a description of the properties and effects of Phenacetin.

Here is the content list:

l Physical and chemical properties

l Carcinogenicity

l Action

Physical and chemical properties

Phenacetin is a white, odorless, monoclinic prism at room temperature. The solubility in water is 0.076 g/100 ml and it is insoluble in water. No color when dissolved in concentrated sulphuric acid, orange-yellow when nitric acid is added to the solution. Odorless, slightly bitter. Phenacetin has a melting point of 133-136 °C and a boiling point of 132 °C/4 mm Hg. It has a density of approximately 1.1248, a refractive index of 1.5710, and a flashpoint of 2 °C. It requires hermetic drying and storage at room temperature. Phenacetin is chemically stable and is incompatible with strong oxidizing agents and strong acids. Phenacetin is soluble in water (more soluble in hot water than cold water), alcohol, glycerol, and acetone, and slightly soluble in benzene. Phenacetin is unstable to oxidizing agents, iodine, and nitrating agents (IARC 1977).

Carcinogenicity

Cancer studies in experimental animals

In an 18-month carcinogenicity study, dietary administration of Phenacetin at 2.5% induced pelvic renal cell carcinoma and bladder metastatic cell carcinoma in rats, with a higher incidence of tumors in males than in females. In another long-term carcinogenicity study, dietary administration of 0.535% Phenacetin for 117 weeks induced renal pelvic tumors in male rats. In B6C3F1 mice maintained on a diet containing 1.25% or 0.6% Phenacetin for 96 weeks, dose-related induction of renal tumors was observed in male mice and bladder hyperplastic lesions were seen in mice of either sex fed 1.25% Phenacetin.

Human cancer studies

Many cases of renal cancer (metastatic cell carcinoma of the renal pelvis) have been reported in patients receiving large amounts of an analgesic mixture containing Phenacetin. However, it is not possible to specify which components of the mixture are carcinogenic.

Two early case-control studies from the USA and Australia reported on patients with renal cancer diagnosed in the late 1970s and early 1980s, a decade after Phenacetin was withdrawn from these markets. The reports stated that people who routinely used preparations containing Phenacetin had an increased risk of kidney cancer. However, the results of the US study were not statistically significant and the Australian study did not show any positive trend in increasing risk by increasing cumulative intake of Phenacetin.

Action

Phenacetin is used to treat fever, headache, neuralgia, and muscle and joint pain. Phenacetin is an antipyretic and analgesic, which is also known as acetaminophen, and can be turned into acetaminophen in the body to provide an antipyretic and analgesic effect. A small portion of it can be deacetylated to acetaminophen, which is further metabolized in the body to iminoquinone, which oxidizes hemoglobin to methemoglobin, leading to hypoxia and cyanosis in large amounts. However, due to the toxic side effects and the rapid development of similar drugs, it is no longer used alone, but only as a raw material in combination with other drugs.

Mulei (Wuhan) New Material Technology Co. Ltd. specializes in the manufacture of Phenacetin.