Insulin

The original peptide medicine. More than a century of clinical use. It is a life-saving hormone replacement, not a performance or fat-loss tool — hypoglycemia from misuse is an emergency.

The endogenous peptide hormone of beta cells. Therapeutic insulins bind the insulin receptor, driving glucose uptake and suppressing hepatic glucose output. Analogs alter onset and duration via sequence or formulation changes.

Evidence is as strong as medicine gets: physiology, RCTs, and decades of outcomes data for type 1 and insulin-requiring type 2 diabetes. Analog insulins have their own comparative trials on hypoglycemia and A1c.

FDA-approved in many analog and human forms. Prescription. Some older formulations have OTC pathways in the US; that does not make unsupervised use safe.

Prescription analog insulins from a pharmacy are the standard path. In the US, some older human insulins (e.g. Regular, NPH) have OTC pharmacy pathways — that is a safety net, not a suggestion to self-design a regimen. Technique training belongs with a clinician.

Same four pathways as the Sourcing guide.

Generally covered as a diabetes essential, with copay caps and manufacturer programs in flux. Analog vs human, vial vs pen, and preferred-brand lists change yearly. Medicare Part D and many states have insulin cost-sharing limits.

Unregulated 'research insulin' is a medical emergency waiting to happen. Counterfeit pens exist. Do not buy insulin from social media.

Strand does not list vendors. See the grey market.

Hypoglycemia and weight gain are the dominant risks. Technique, timing, and carbohydrate intake matter. Never used for body-composition experiments outside a clinic.

• Hypoglycemia can kill. Weight gain is common.
• Wrong product, expired product, or heat-damaged product is a dosing error.
• Never used as a fat-loss or performance tool.

• DCCT · 1993 · N Engl J Med

  Diabetes Control and Complications Trial Research Group. The effect of intensive treatment of diabetes. PMID 8366922.

• ADA Standards of Care

  Pharmacologic approaches to glycemic treatment — annual living standards.