Hello,
Thanks for the query.
Herbalife is a line of herbal supplements and Like with any other weight loss product, Herbalife products have potential side effects you should be aware of.
There are various constituents of Herbal life products like 
Caffeine,Soya and Shell fish,Lead etc ,which can cause problem in an individual.

Products of herbalife are unregulated dietary supplements. Even though they are natural and safe but they tend to cause many side effects such as primary pulmonary hypertension, liver damage, and even death.

Many users of Herbalife have filed lawsuits and complaints about side effects they experienced when using the products. Headaches, constipation, diarrhea, lightheadedness, nausea, and stomach upset are some reported side effects. 

I would be very wary of using such products and if you are really very keen to use these products,then you should consult your doctor and discuss about the ingredients of these herbal supplements and their possible interaction with the drugs you are already using for chronic pain disorder.
I hope it helps however you may revert to me for any further query.
Best of luck
Thanks

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