Pfizer Inc. is an American pharmaceutical company with headquarters on 235 East 42nd Street, New York City. The company was co- founded by Charles Pfizer and Charles F. Erhart in the year 1849 and was known as Charles Pfizer & Company. The company was incorporated in the year 1942 with a capital of 2 million dollars. Charles Pfizer borrowed from his father, a sum of 2,500 dollars, and bought a commercial building in Williamsburg, Brooklyn. Afterwards, he co-founded Chas. Pfizer & Co. Inc. The company had its headquartered on Bartlett Street in New York and was involved in the production of chemical compounds. They produced a product called santonin which was an antiparasitic. Although the launch of santonin can be called successful, it was the manufacture of their citric acid led to their expansion significantly in the 80s. The company later shifted its headquarters to Manhattan in the year 1881. The shortage of calcium citrate during the time of the First World War forced the company to look for an alternative ingredient for citric acid production. The result of this was the development of a fungal fermentation technique which could be used to ferment sugar for the production of the citric acid. The company went on to produce antibiotics and penicillin on a large scale. With the finding of oxytetracycline in the year 1950, the company changed from a chemical-producing company to a research-based one.

The company specializes in the areas of immunology, inflammation, oncology, pain management, cancer, cardiovascular disorders, endocrinology, neurology and rare diseases.

The company has its manufacturing facilities located at Kalamazoo in Michigan, Andover in Massachusetts, Franklin in Ohio, McPherson in Kansas, Middleton in Wisconsin, Pearl River in New York, Rochester in Michigan, Rocky Mount in North Carolina, Sanford, North Carolina and St. Louis in Missouri. The company also has manufacturing units in India, China, Japan, Ireland, Italy, Belgium, Germany, Singapore, and the US. Pfizer Inc. supplies its products to a number of countries including North America, South America, Asia-Pacific, Australia, Europe, Africa and the Middle East.

Some of the top products of the company include PREVENAR-13, BECOSULES, DOLONEX, COREX-DX, MAGNEX, MINIPRESS-XL, MUCAINE, WYSOLONE, GELUSIL-MPS, ELIQUIS, DALACIN C, MERONEM, FOLVITE, OVRAL-L, LYRICA, COREX T, ATIVAN, SOLU-MEDROL, AUTRIN, BECOSULES-Z, PREMARIN, MEDROL, NEKSIUM, CITRALKA, OVRAL-G, DAXID, PACITANE, PALBACE, VIAGRA, FRAGMIN, HETRAZAN, AMLOGARD, FOLVITE-MB, ZAVICEFTA, LOETTE, XELJANZ, SUTENT, BRONCOREX, MAGNAMYCIN, BECOSULES PERFORMN, XALATAN, ERAXIS, FOLVITE ACTIVE, ATGAM, PITOCIN, DEPO-PROVERA, TARGIT, PENIDURE LA, ENBREL and BECOTROL.