Congratulations on your weight loss. One thing many people don't anticipate is that after losing a significant amount of weight, certain facial and neck structures that were previously less noticeable can become much more visible. The platysma muscles are a common example. Based on your description, Botox can be a very effective treatment if the issue is truly prominent platysmal banding caused by muscle activity. When these bands become more visible during smiling, speaking, grimacing, or other facial expressions, it suggests that the muscle is playing a significant role. Relaxing the muscle with Botox can soften the appearance of those vertical cords and create a smoother neck contour. The fact that you're now noticing some banding even at rest is important. In many patients, this is still largely muscle-related and responds well to treatment. However, after weight loss, there may also be some skin laxity or loss of soft tissue volume contributing to the appearance. Botox can improve the muscular component, but it won't tighten loose skin or restore lost volume. For younger patients such as yourself, treatment of the central platysmal bands alone is often sufficient and can produce a natural-looking improvement. The results are temporary, typically lasting several months before maintenance treatment is needed. One thing I would emphasize is that the best results occur when the bands are accurately identified as the primary cause of the concern. In patients whose neck appearance is driven more by skin laxity than muscle activity, Botox alone may provide only partial improvement. From what you've described—especially the increased visibility when smiling and contracting your neck muscles—you sound like someone who could potentially respond quite well to Botox treatment of the anterior platysmal bands. The degree of improvement would ultimately depend on how much of the prominence is due to muscle activity versus changes in skin and soft tissue following your weight loss.