The word "hopped-up" is often used to describe someone who is energetic or excited. However, there are a few antonyms that can be used in its place, depending on the context. "Laid-back" is a term that refers to someone who is calm and relaxed. "Serene" or "placid" can also be used to describe someone who is peaceful and content. If someone is not overly excited, "calm" or "composed" might be appropriate. If someone is not under the influence of drugs or alcohol, "sober" is a good antonym. These words can help provide a more accurate description of someone's behavior or demeanor.