This medication is most effective when used regularly. The dosage must be kept constant for the drug's effects to remain stable. It is best to take your daily Gabapentin 600mg Tabs at the same time(s) each day. If you use this drug thrice daily to control your seizures, the interval between doses should not exceed 12 hours. Do not increase your dosage or length of treatment without first consulting your physician. Your condition may not improve quickly, and you may have serious side effects.