Ativan withdrawal symptoms vary by phase, but generally include flu-like symptoms such as headaches, sweating, nausea, vomiting, increased blood pressure. Even after taking Lorazepam, also known as Ativan, for a short amount of time; Lorazepam withdrawal symptoms can last for weeks, months or years without. As a side effect of their therapeutic effects, benzodiazepines like Ativan also Withdrawal symptoms can be reversed very quickly if the individual begins taking.