Brief Answer:
I do not think so

Detailed Answer:
Hi,
Thanks for usinghealthcaremagic.

Yes I agree that wellbutrin is antidepressant but it is not true that it does not have side effects. Like all other drugs wellbutrin is associated with various side effects.
The most common side effects with wellbutrin are
1. Anxiety
2. dry mouth
3. hyperventilation
4. irregular heartbeats
5. irritability
6. restlessness
7. shaking
8. shortness of breath
9.trouble sleeping
10. Abdominal or stomach pain
11. constipation
12. decrease in appetite
13. dizziness
14. increased sweating
15. weight loss (unusual)

Other side effects which are less common include
1. Buzzing or ringing in the ears
2. headache (severe)
3. skin rash, hives, or itching

You can note from the above list that weight loss is a side effect of wellbutrin which is quite unusual, It is proposed that weight loss occurs due to decreased appetite.

Having said this every medicine including anti depressant have both uses and off label uses. I am not aware that why your psychiatrist prescribed Cymbalta for you. It is used in depression, anxiety disorder, diabetic neuropathy and somatization disorder. The wellbutrin is useful only for depression out of these four indications. It is OK to try wellbutrin instead of cymbalta in case of depression(as both are indicated) but the use of wellbutrin is not indicated if you got cymbalta prescription for anxiety or diabetic neuropathy or somatization disorder.
As I can see you are concerned with weight gain but please note both the medicines which you are taking is not associated with weight gain. Changing medicine is unlikely to serve purpose. What you need to focus is healthy life style and diet which are more likely to help you.

'Hope I have answered your query. If you have any further questions I will be happy to help".
Thanks

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