What are the negative effects or side effects of microdosing?

In the Thomas Anderson study, the top 3 most commonly reported challenges were:

• Concerns about legality (this ranked first by a significant margin)
• Physical Discomfort, such as upset stomach
• "Other Concerns" about the long-term consequences of microdosing, due to lack of scientific research

In general, the most commonly reported side effects from microdosing includes:

• Muscle cramps
• Upset stomach
• Dizziness
• Anxiety
• Overstimulation
• Irritability or agitation on "off" days
• Paranoia (related to the legality)