While difficulty getting or keeping an erection is not among the most common side effects of Zonegran (zonisamide), sexual side effects can occasionally occur. Other factors, including stress or the underlying condition itself, can also play a role. Please don't be discouraged, as there are many ways to manage this. I gently encourage you to discuss this openly with your prescribing doctor. They can help identify the cause and safely adjust your treatment or explore alternative options to help you feel like yourself again.