Hello and Welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice. Beta-blockers may cause various side effects. Some of them are common in this drug-class, others are inherent to each particular member of the class. The most obvious side effects are hypotension and bradycardia. I ve used quotation marks because these effects are actually the reason we use them in most cases. Other side effects include nightmares, fatigue, cold extremities, weight gain, etc. My answer can t be more specific or detailed because there are many beta-blockers and the side effects may differ. I ve mentioned some of the most common ones that apply for most of them. For example there are beta-blockers that don t cause nightmares but most of them may do so. Some beta-blockers may cause skin reactions but most are not likely to do so, etc. Hope I have answered your query. Let me know if I can assist you further.