Semax vs Tesamorelin

Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.

SemaxTesamorelin
CategoryPeptidesPeptides
Standard DoseResearch indicates 200-600 mcg daily via intranasal administration (0.1% solution, 2-3 drops per nostril).Research indicates 2 mg administered once daily via subcutaneous injection (FDA-approved dose for HIV lipodystrophy).
TimingMorning and early afternoon dosing (avoid evening — may cause stimulation/insomnia). Intranasal preferred for rapid CNS delivery.Morning administration on empty stomach. Consistent daily timing recommended.
Cycle Duration10-14 day cycles with equal rest periods. Some protocols use 3-5 day on / 2 day off patterns.26+ weeks in clinical trials. Long-term use is common; effects are not sustained after discontinuation.
Evidence Levelmoderate_humanStrong (FDA-approved indication), Moderate (longevity)
A

Semax

Peptides

Mechanism

Semax (Met-Glu-His-Phe-Pro-Gly-Pro) is a synthetic heptapeptide analog of the ACTH(4-10) fragment that rapidly upregulates brain-derived neurotrophic factor (BDNF) and its signaling receptor TrkB in the hippocampus (1.4-fold BDNF protein increase, 3-fold exon III BDNF mRNA increase). It activates dopaminergic and serotonergic brain systems, enhances neurotrophin gene expression (BDNF, NGF), and modulates intracellular calcium dynamics in brain neurons. Semax lacks ACTH's corticotropic activity, acting purely as a nootropic/neuroprotective agent.

Standard Dosing

Research indicates 200-600 mcg daily via intranasal administration (0.1% solution, 2-3 drops per nostril).

Timing

Morning and early afternoon dosing (avoid evening — may cause stimulation/insomnia). Intranasal preferred for rapid CNS delivery.

Cycle Duration

10-14 day cycles with equal rest periods. Some protocols use 3-5 day on / 2 day off patterns.

Side Effects

  • Nasal irritation (intranasal route)
  • Mild headache
  • Stimulation/insomnia if dosed late
  • Irritability at high doses
  • Hair loss (anecdotal at high doses)

Contraindications

  • Seizure disorders
  • Acute psychosis or mania
  • Pregnancy and breastfeeding
  • Severe hypertension

Best Stacking Partners

SelankP21Noopept
B

Tesamorelin

Peptides

Mechanism

Tesamorelin is an FDA-approved synthetic 44-amino acid GHRH analog with a trans-3-hexenoic acid modification at the N-terminal tyrosine that confers resistance to DPP-IV degradation. It binds GHRH receptors on anterior pituitary somatotrophs, stimulating endogenous GH production and secretion while maintaining pulsatile release patterns. Tesamorelin selectively reduces visceral adipose tissue (15-20% reduction in trials) while preserving subcutaneous fat, and markedly increases plasma GH and IGF-1 levels with once-daily dosing.

Standard Dosing

Research indicates 2 mg administered once daily via subcutaneous injection (FDA-approved dose for HIV lipodystrophy).

Timing

Morning administration on empty stomach. Consistent daily timing recommended.

Cycle Duration

26+ weeks in clinical trials. Long-term use is common; effects are not sustained after discontinuation.

Side Effects

  • Injection site reactions (erythema, pruritus)
  • Arthralgia
  • Peripheral edema
  • Myalgia
  • Paresthesia
  • Elevated blood glucose

Contraindications

  • Active cancer or pituitary tumors
  • Pregnancy (Category X)
  • Hypersensitivity to GHRH analogs
  • Disruption of hypothalamic-pituitary axis from surgery/radiation
  • Active cancer
  • Pregnancy
  • Pituitary surgery or disease

Best Stacking Partners

IpamorelinAOD-9604

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