I Take it as does my son for pain due to peripheral neuropathy. We both take a dosage of 1800 mg/day. I have not noticed any side effects. The following quote comes from the source cited below.
"SIDE EFFECTS: Drowsiness, dizziness, unsteadiness, fatigue, vision changes, weight gain, nausea, dry mouth, or constipation may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly. Tell your doctor immediately if any of these serious side effects occur: tremor or shaking, swollen arms/legs. Tell your doctor immediately if any of these unlikely but serious side effects occur: loss of coordination, mental/mood changes. Tell your doctor immediately if any of these highly unlikely but very serious side effects occur: persistent sore throat/fever/cough, unusual bleeding/bruising, pain/redness of arms or legs, chest pain, trouble breathing, fast/slow/irregular heartbeat, hearing loss, stomach/abdominal pain. If you notice other effects not listed above, contact your doctor or pharmacist."
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