Severe acid-base and/or electrolyte abnormalities may potentiate or cause resistance to the neuromuscular blocking action of ZEMURON. No data are available in such patients, and no dosing recommendations can be made.ZEMURON, which has an acid pH, should not be mixed with alkaline solutions (e.g. barbiturate solutions) in the same syringe or administered simultaneously during intravenous infusion through the same needle. ZEMURON may be associated with increased pulmonary vascular resistance, so caution is appropriate in patients with pulmonary hypertension or valvular heart disease. In patients with myasthenia gravis or myasthenic (Eaton-Lambert) syndrome, small doses of non-depolarizing neuromuscular blocking agents may have profound effects. In such patients, a peripheral nerve stimulator and use of a small test dose may be of value in monitoring the response to administration of muscle relaxants. If extravasation occurs, it may be associated with signs or symptoms of local irritation. The injection or infusion should be terminated immediately and restarted in another vein. In clinical trials, the most common adverse reactions (2 percent) are transient hypotension and hypertension. There are no controlled studies documenting the use of ZEMURON before or after other non-depolarizing muscle relaxants. Interactions have been observed when other non-depolarizing muscle relaxants have been administered in succession. The use of ZEMURON before succinylcholine, for the purpose of attenuating some of the side effects of succinylcholine, has not been studied. Please see U.S. prescribing information at: http://www.merck.com/product/usa/pi_circulars/z/zemuron/zemuron_pi.pdf. Merck's Commitment to Hospital-Based Medicine Merck is committed to scientific excellence, and the discovery and development of innovative treatments for patient care in hospitals. We strive to develop new solutions to help our hospital-based customers deliver quality care to their patients. About Merck Today's Merck is a global healthcare leader working to help the world be well. Merck is known as MSD outside the United States and Canada. Through our prescription medicines, vaccines, biologic therapies, and consumer care and animal health products, we work with customers and operate in more than 140 countries to deliver innovative health solutions. We also demonstrate our commitment to increasing access to healthcare through far-reaching policies, programs and partnerships. For more information, visit www.merck.com and connect with us on Twitter, Facebook and YouTube. Forward-Looking Statement This news release includes “forward-looking statements” within the meaning of the safe harbor provisions of the United States Private Securities Litigation Reform Act of 1995. These statements are based upon the current beliefs and expectations of Merck’s management and are subject to significant risks and uncertainties. There can be no guarantees with respect to pipeline candidates that the candidates will receive the necessary regulatory approvals or that they will be commercially successful. If underlying assumptions prove inaccurate or risks or uncertainties materialize, actual results may differ materially from those set forth in the forward-looking statements.