Expected Ativan Side Effects: Drowsiness and mild nervous system depression during the day following use at bedtime are normal and expected side effects of this medication. Normal use may cause mild central nervous system depression, but dosage should be managed to minimize this. Do not drive or perform any other potentially hazardous activities until you are familiar with your reaction to this medication and know how long it takes to clear from your body. Withdrawal: If you take Ativan for longer than four weeks, or at higher dosages, physical withdrawal symptoms are a possible result. Ativan treatment should never be stopped abruptly; instead, you should gradually decrease your dose according to the advice of your doctor. Possible effects include insomnia, ringing in the ears, shaking, tremors, sweating, and nausea, depending on the dosage and length of use before withdrawal. THis is a very effective drug for anxiety. Withdrawl symptoms can be evident and unpleasent if I've used my prescription too quickly in a given month. I take 60 .5mg tablets every thirty days. This medicine has wonderful potential to help anxious people feel comfortable; however, it must be used with descretion.