The Wall Street Journal had an article this week about the growing realization that benzodiazepines can cause major problems when trying to quit using them. The symptoms described aren't all that different from what I experienced when I stopped Effexor. The article also details serious physical problems for those using them, some of them not unlike what you describe. The article only briefly mentions lorazepam and focuses instead on Xanax, but the problems it discusses seem to seep over into all the different benzodiazepines. It's behind a paywall, as is everything on that paper, but if you have a subscription it's worth reading. If you don't, it's probable that your library carries it. Based on what I read, it sounds like getting a doctor involved in tapering him off would be wise.
https://www.wsj.com/health/wellness/xanax-drug-benzodiazepines-research-harm-7a60f236?mod=hp_lead_pos7