On CNBC’s “Mad Money Lightning Round,” Jim Cramer recommended buying Merck & Co., Inc. (NYSE:MRK). “I have tremendous, tremendous faith in what Robert Davis [CEO of Merck] is doing,” he added. When asked about Teladoc Health, Inc (NYSE:TDOC), he said, “What’s going on there, right now we’ve got this Cathie Wood, she sells the stock almost every day. She bought it much higher, it’s really painful to watch.” Fortinet, Inc. (NASDAQ:FTNT) reported a “very good” quarter, he said. “I remain committed to Nikesh Arora [CEO of Palo Alto Networks] and Palo Alto Networks (NASDAQ:PANW), which I think is d…