Lorazepam 1mg and mg Tablets. Read all of this leaflet If any of the side-effects get serious, or if you notice any side-effects not listed in this leaflet, please. Side Effects. Drowsiness, dizziness, loss of coordination, headache, nausea, blurred vision, change in sexual interest/ability, constipation, heartburn, or change in appetite may occur. Learn about the potential side effects of lorazepam. Includes common and rare side effects information for consumers and healthcare professionals.