It is available in certain clinics under compounding programs, but quality and consistency can vary widely depending on the source (FDA PCAC briefingcompounding context)
Ermens AAM, Vlasveld LT, Lindemans J

Additional caution or monitoring may be appropriate in research settings involving: Pregnancy- or lactation-related research models, where limited safety data is available Active cancer-, tumor-, or abnormal proliferative research models, where NAD-related and metabolic-signaling pathways may influence cellular-signaling mechanisms Cardiovascular- or uncontrolled-hypertension research models, where metabolic-pathway modulation may influence cardiovascular-related biomarkers in some experimental settings Thyroid-related or endocrine research models, where metabolic-pathway investigations may influence endocrine-related observations Diabetes- or glucose-regulation research models, where insulin- and glucose-related pathways may warrant closer monitoring in experimental settings Moderate to severe hepatic- or renal-impairment research models, where compound metabolism or clearance mechanisms may be altered Autoimmune- or inflammatory-response research models, where immune-metabolic signaling pathways may influence inflammatory-related biomarkers or cytokine observations Research conditions, dosage ranges, administration frequency, protocol duration, and concurrent compounds may influence tolerability observations across experimental settings

If you are still experiencing significant nausea, vomiting, or diarrhea at the end of a 4-week dose block, stay at the current dose for another 2-4 weeks before attempting the next increase
Richland obtained his Doctor of Medicine (M.D.) degree from the prestigious program at Saint Louis University (SLU) School of Medicine in 2013
Read the full dosage guide