Hello and Welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice. Nicotine patch doesn t cause erectile dysfunction. It could be due to your withdrawal from nicotine. Your body will experience some adjustment problems when you are about to wean off from a substance like nicotine. Nothing to worry much and you will be fine in couple of days. Do not restart smoking. Hope I have answered your query. Let me know if I can assist you further.