HCG (Human Chorionic Gonadotropin)
Gonadotropin
Also known as Human Chorionic Gonadotropin, HCG
Half-life
~36 hours
What is HCG (Human Chorionic Gonadotropin)?
Peptide hormone that mimics LH. Maintains testicular function and size during suppressive cycles.
How HCG (Human Chorionic Gonadotropin) works
Mimics luteinizing hormone (LH) by binding testicular LH receptors to stimulate testosterone production and spermatogenesis, preserving testicular volume and function during suppressive cycles.
Benefits & uses
Common uses: Testicular maintenance on cycle, fertility preservation, PCT preparation, natural T recovery.
HCG (Human Chorionic Gonadotropin) dosage
Protokol doesn't recommend doses for prescription or controlled compounds. Any figures below are reference or observational reports — dosing should be set with a qualified clinician.
- Reference range
- Literature reports ~500 IU 2×/week (on TRT) up to ~1500–2000 IU 2–3×/week (monotherapy); SubQClinical or reference range, not a personal recommendation.
HCG (Human Chorionic Gonadotropin) half-life
~36 hours (biological half-life ~24–36 h)
HCG (Human Chorionic Gonadotropin) side effects
Desensitization of LH receptors with prolonged high-dose use. Estrogen conversion.
- LH receptor desensitization with chronic high-dose use
- Aromatization to estrogen (may require AI co-administration)
- Gynecomastia at high doses
- Testicular pain or swelling (uncommon)
- Mood fluctuation from testosterone and estrogen surges
- Estrogen increase
- Acne
- Water retention
- Injection-site reactions
Warnings & monitoring
- Prescription medication, injectable — requires a doctor. Reconstituted product must be refrigerated and used within ~30–60 days.
Monitoring: Hormone panel; estradiol can rise (may need AI).
Preparation & storage
- Reconstitution
- Reconstitute lyophilized HCG with BAC water; refrigerate, use within ~30–60 days
- Storage
- Lyophilized: room temp or refrigerate. Reconstituted: refrigerate (2–8 °C), stable ~30 days.
HCG (Human Chorionic Gonadotropin) interactions
with Clomid
Caution · mildHCG should precede Clomid in PCT to prime the testes, but concurrent long-term use can desensitize LH receptors and blunt the SERM effect.
Timing: Run HCG first for 2–3 weeks before adding Clomid; do not use long-term together
with Gonadorelin
Caution · mildGonadorelin pulses upstream (GnRH→LH/FSH); HCG mimics LH downstream. Stacking is mostly redundant; pick based on long-cycle vs short-cycle goals.
Timing: Choose one per protocol
with Kisspeptin-10
Caution · moderateBoth drive LH/FSH release. Stacking causes excessive testicular stimulation and can overshoot E2.
Timing: Do not co-administer; choose one HPGA stimulant
with Clomid
Compatible · lowHCG maintains testicular sensitivity during suppression; Clomid then restores pituitary LH/FSH drive. Sequential use is more effective than concurrent — HCG desensitizes LH receptors if continued during PCT.
Timing: Run HCG during cycle/cruise, stop 4–5 days before starting Clomid PCT
with Clomid
CompatibleHCG mimics LH, preserving Leydig cell function during suppression. Clomid then restarts endogenous LH/FSH post-cycle.
Timing: HCG during cycle to maintain testicular volume; Clomid in PCT
with Testosterone
CompatibleHCG maintains testicular size and LH receptor sensitivity during TRT or blast cycles. Stimulates intratesticular testosterone production. Standard supportive compound.
Timing: HCG typically used 2×/week alongside testosterone; cease before PCT
with Testosterone
CompatibleHCG mimics LH to keep the testes active and prevent atrophy during testosterone suppression, significantly easing recovery post-cycle.
Timing: Use HCG 2–3x per week alongside testosterone throughout the cycle
Commonly stacked with
Track HCG (Human Chorionic Gonadotropin) in Protokol.
Log doses, model half-lives, check interactions, and line it all up against your bloodwork. Free on iPhone and Android.
