Sertraline - What is the best medicine for anxieties without gaining weight?

Hi, joelanna!
If there was such a thing we'd all be taking it!!!
Unfortunately, most, if not all, antidepressant/anxiolytics have the potential to cause weight changes in about 1-10% of users. Some of these changes may be weight loss but weight gain is much more common because of metabolic changes that affect appetite and fat storage mechanisms.
There are the benzodiazepines which may be less likely to cause weight gain but they are highly addictive and can cause serious short and long term side effects.
Another medication that's often prescribed is buspirone which is less likely to make you gain weight.
In most cases any weight gain is usually not clinically significant and it's also a matter of trial and error because gaining weight on one medication doesn't necessarily mean you'll gain on another.
Best regards and I hope you find the right one for you.,