I took 5-HTP longterm (two years) and started experiencing panic attacks, among other symptoms. I had to stop. I had supposed this to be a natural supplement without side effects, but I was wrong. I suppose each person is quite unique, so your mileage will vary.
Two years it's kinda long to take anything really. You can mess yourself up even if you just drink specific herbal tea for that long if you are unlucky.
Yes it definitely made me reevaluate my vitamin routine. I cut back most supplements and only take fish oil and vitamin D in winter now. I even cut out the caffeine and feel MUCH more relaxed.
