The phrase "low tolerance" means that someone has little patience or ability to withstand or accept certain things, situations, or behaviors. Full definition
It has a very low tolerance for heat and, when heated above its threshold, breaks down and produces potentially harmful chemicals. (mindbodygreen.com)
If the patient has very low tolerance of anxiety, a treatment process in group or individual therapy may be required first to build this up before the emotions can be experienced. (cebc4cw.org)
Dogs have a much lower tolerance for caffeine than we do. (petconsider.com)