A lab-made copy of the brain signal that prompts growth hormone release. Best-supported effect: marked loss of deep abdominal fat, less liver fat, modest lean-tissue gain. Nearly all trials enrolled people with a chronic immune-system virus, and the main ones were company-funded. Benefit fades once treatment stops. Whether it lengthens life remains genuinely open. (Full Review)

Protocol

Standard approved protocol

1.28 mg daily

Egrifta WR, injected subcutaneously into the abdomen once daily; predecessor formulations were dosed at 2 mg daily. Off-label practice uses 1 to 2 mg daily, titrated to a target IGF-1 in the upper half of the age-adjusted reference range.

Best time of day

Bedtime

Typically 30 minutes before sleep, on an empty stomach, to amplify the largest physiological growth hormone pulse. Single daily dosing only; splitting the dose is counterproductive and untested.

Injection technique

Rotate abdominal quadrants

Subcutaneous, rotating quadrants each day, avoiding the 5 cm around the navel and any scarred, bruised, or reactive skin. Reconstituted solution is inspected for particles before use.

Time to effect

Deep abdominal fat

3 to 6 months

Detectable by imaging at about 3 months, reaching most of its effect by 6 months, with further consolidation to 12 months.

Liver fat

12 months

Liver fat changes were measured at 12 months in the trial that established them.

IGF-1

2 to 4 weeks

Rises within days and is measurable at 2 to 4 weeks. Scale weight is a poor tracker throughout.

Benefits

High: Reduction of deep abdominal fat; reduction of liver fat; increase in lean body mass; restoration of insulin-like growth factor 1 to the upper physiological range

Medium: Improvement in blood lipids; slowing of liver fibrosis progression; improvement in muscle quality and reduction of fat infiltration in muscle; improvement in self-rated body composition and body image

Low: Conflicted evidence on cognitive performance; reduction in inflammatory markers; improvement in mitochondrial function

Speculative: Improved sleep depth; accelerated peripheral nerve regeneration; preservation of lean mass alongside incretin-based weight loss; skin quality and recovery from training

Contraindications

Disruption of the hypothalamic-pituitary axis (hypophysectomy, hypopituitarism, pituitary tumor or surgery, cranial irradiation, significant head trauma)

Active or suspected malignancy, or any treated within the preceding 24 months (other than non-melanoma skin cancer)

Known hypersensitivity to tesamorelin or to mannitol

Pregnancy and breastfeeding

Poorly controlled diabetes (HbA1c above 8%, or active proliferative or severe non-proliferative retinopathy)

IGF-1 already elevated (z-score above 2.0 before treatment)

Acute critical illness (open-heart or abdominal surgery, multiple accidental trauma, acute respiratory failure)

Unstable cardiac disease (active or unstable coronary artery disease, chest pain suspicious for angina, serious arrhythmia)

Under 18 years of age

Key Interactions

Glucocorticoids (prednisone, hydrocortisone, cortisone acetate, dexamethasone)

Glucose-lowering agents (metformin, sulfonylureas such as glipizide, insulin, GLP-1 receptor agonists such as semaglutide)

Thyroid hormone replacement (levothyroxine, liothyronine)

Oral estrogens (combined oral contraceptives, oral estradiol)

Other growth hormone secretagogues and growth hormone itself (sermorelin, CJC-1295, ipamorelin, GHRP-2, ibutamoren, somatropin)

Over-the-counter non-steroidal anti-inflammatory drugs (ibuprofen, naproxen)

Over-the-counter melatonin and sedative sleep aids

Supplements with additive growth hormone or IGF-1 effects (L-Arginine, L-Ornithine, glycine, gamma-aminobutyric acid, alpha-GPC, colostrum and deer antler velvet extracts)

Supplements affecting blood glucose (berberine, chromium, alpha-lipoic acid, inositol)

CYP3A4 substrates (simvastatin, ritonavir)

Risk & Side Effects

High: Injection site reactions; joint and muscle pain; fluid retention and peripheral edema; conflicted evidence on an early rise in blood glucose; anti-tesamorelin antibody formation

Medium: Loss of benefit after discontinuation; paresthesia, hypoesthesia, and carpal tunnel syndrome; hypersensitivity reactions; gastrointestinal effects; higher discontinuation rate on treatment

Low: Theoretical promotion of occult neoplasia; worsening of diabetic retinopathy; worsening of sleep-disordered breathing; suppression of circulating cortisol through 11β-HSD1 inhibition

Speculative: Unfavorable long-term effect on longevity from sustained IGF-1 elevation; acromegaly-like soft tissue changes with supraphysiological off-label dosing; cardiac structural change

Monitoring

Marker	Target	Why
IGF-1	Mid to upper-middle of the age- and sex-adjusted range; z-score between 0 and +1.5	The titration target and the proof the drug is working
Fasting glucose	75-85 mg/dL (4.2-4.7 mmol/L)	Detects the early insulin-antagonist effect of growth hormone
HbA1c	4.8-5.3%	Confirms the early glucose rise did not become persistent
Fasting insulin and HOMA-IR	Insulin below 5 µIU/mL; HOMA-IR below 1.0	Detects loss of insulin sensitivity before glucose moves
ALT	Below 25 U/L in men, below 20 U/L in women	Tracks the liver-fat benefit
Triglycerides	Below 80 mg/dL (0.9 mmol/L)	The lipid fraction most responsive to visceral fat loss
hs-CRP	Below 0.5 mg/L	Tracks the inflammatory component of visceral fat
TSH with free T4	TSH 0.5-2.0 mIU/L with free T4 in the upper half of range	Growth hormone alters thyroid hormone conversion and can unmask marginal deficiency
Visceral fat area	Reduction of at least 8% from baseline at 6 months	The primary definition of response used in the trials
Hepatic fat fraction	Below 5%, or a relative reduction of at least 30%	The endpoint if fatty liver is the reason for treatment
Waist circumference	Below 94 cm in men, below 80 cm in women	A zero-cost proxy that tracks the imaging endpoint

Cadence: Front-loaded. IGF-1 and fasting glucose at 2 and 6 weeks, then IGF-1, glucose, and HbA1c every 3 months; lipids and liver enzymes at 6 months and then every 6 to 12 months; repeat visceral fat imaging at 6 months and hepatic fat imaging at 12 months; thyroid function at baseline and 3 months; cancer screening annually.

Qualitative Assessment

Morning ankle and hand swelling: the earliest and most reliable sign of fluid retention
Joint stiffness and aching, particularly in the hands and knees: signals that the dose is above what is comfortable
Numbness or tingling in the fingers, especially on waking: the warning sign for median nerve compression at the wrist
Depth and continuity of sleep: a possible benefit and, with snoring, a warning about airway effects
Waistband fit: often perceptible before imaging or the tape measure confirms it
Recovery between training sessions and daytime energy: least supported by controlled data, so a written record beats recollection
Injection site condition: persistent redness or nodules at rotated sites indicate a technique or product problem

Tesamorelin for Health & Longevity

Protocol

Benefits

Risk & Side Effects

Monitoring

Qualitative Assessment