The half-life of Ativan 1mg is about 12 hours. Buy Ativan 1mg online for its fast-acting effects, it starts in 15 to 30 minutes and lasts for up to 12- 24 hours, and it has a long half-life. The medication elimination of the Ativan depends on a person's metabolism, age, frequency of dose, and length of amount. According to drug tests of most people, the detectability of Ativan in urine is up to six days, blood up to three days, hair about 30 days, and saliva up to 8 hours.