Peptide Dosing: Why Body Weight Matters
Peptide dosing is typically calculated on a per-kilogram basis (mcg/kg) because the effective concentration in your body depends on your total mass. A 60 kg person and a 100 kg person need different absolute doses to achieve similar blood concentrations and effects.
Understanding Dose Ranges
Most peptides have published dose ranges from research studies and clinical trials. We categorize these into three tiers:
- Conservative (Low): The lower end of studied doses. A good starting point to assess tolerance and individual response.
- Standard (Medium): The most commonly used dose range in research. Balances effectiveness with manageable side effects.
- Aggressive (High): The upper end of studied doses. Higher risk of side effects; typically used under close medical supervision.
Frequency and Cycling
Different peptides have different administration frequencies based on their half-lives and mechanisms of action. Short half-life peptides like BPC-157 or Ipamorelin may need once or twice daily injections, while long-acting peptides like Semaglutide or CJC-1295 (with DAC) only need weekly administration.
Most peptides are used in cycles — periods of use followed by breaks — to prevent receptor desensitization and maintain effectiveness. Typical cycles range from 4 weeks for healing peptides to ongoing use for metabolic peptides like GLP-1 agonists.
Individual Variation
Response to peptides varies significantly between individuals due to factors like genetics, body composition, existing health conditions, and concurrent medications. Always start at the lower end of the dose range and adjust based on response and tolerance.
Common Peptide Categories
Healing peptides (BPC-157, TB-500) are typically dosed by body weight and used in focused cycles targeting specific injuries or recovery goals.
Growth hormone secretagogues (CJC-1295, Ipamorelin) are used in longer cycles to support GH release, recovery, sleep quality, and body composition.
GLP-1 agonists (Semaglutide, Tirzepatide) require careful dose titration over months and are typically used long-term under medical supervision for metabolic health goals.