I Am Taking Isotretinoin 5 For The Last 5 Months

I am taking isotretinoin 5 for the last 5 months as prescribed by my doctor and it shows very good result but as I stops taking it for 20days acne again starts happening,my Dr. again starts this medicine but as I read about it that patientmuststart it after 1-2month break asper course now I am in doubt that it will cause various side effects to my health?