Pfizer (Inc.) is a U.S. multinational pharmaceutical company. Pfizer is one of the world's largest pharmaceutical companies, ranked 64th in the Fortune 500 list for 2020 for the largest U.S. companies in total revenue, reaching $47.644 billion as of December 31, 2020. Its products include the popular drug Lipitor (Atorvastatin), used to lower LDL cholesterol; Lyrica (Pregabalin) for nerve pain and fibromyalgia; Diflucan (fluconazole), an oral antifungal drug; Zethromax (azithromycin), antibiotic; Viagra (sildenafil) for erectile dysfunction; Celebrex (also Celebra, Celecox), an anti-inflammatory drug; The Prevnar 13, pneumococcal conjugated vaccine. in 2016, Pfizer was expected to merge with Ireland-based Allergan to create "Pfizer plc" in a deal that would have been worth $160 billion. However, the merger was postponed in April 2016, due to new rules from the U.S. Treasury Department against tax fluctuations, a way to avoid taxes by merging with a foreign company. On December 19, 2018, Pfizer announced a joint venture into its consumer healthcare division with British pharmaceutical giant GlaxoSmithKline. Assuming shareholder approvals, the British company will own 68% of the company's shares. episodic. Pfizer was a component of the Dow Jones Industrial Average in 2004-2020, when it was announced that the company would be replaced by Amgen in the Dow. The change came into effect at the beginning of trading on August 31, 2020.