Comparison
Alpha-GPC vs Testosterone
Side-by-side of Alpha-GPC and Testosterone. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
Alpha-GPC
Alpha GPC supplement profile: 300 to 600 mg dosage, acetylcholine synthesis, attention and reaction-time evidence, side effects, and choline donor comparisons.
Testosterone
Testosterone replacement therapy for hypogonadism: TRAVERSE 2023 cardiovascular data, cypionate dosing, body composition gains, Schedule III status.
Effects at a glance
Alpha-GPC
- •Choline donor supplement, roughly 40% choline by weight; crosses blood-brain barrier efficiently
- •Replicated small gains in attention and reaction time at 300 to 600 mg in healthy adults
- •Standard prescription cognitive medication in much of Europe (Gliatilin) at 1,200 mg/day for vascular cognitive impairment
- •ASCOMALVA trial (n=210) showed cognitive preservation when added to donepezil over 24 months
- •Increases acute power output (~14%, single trial) and transient growth hormone secretion at 600 mg
- •TMAO production raises a contested cardiovascular concern at chronic high doses
Testosterone
- •Primary androgen; FDA approved for hypogonadism with confirmed deficiency and symptoms
- •Testosterone Trials (2016) showed sexual function and bone density improvements in older hypogonadal men
- •TRAVERSE 2023 (n=5,246) found non-inferiority on MACE versus placebo, with higher AF and PE rates
- •Schedule III controlled substance in US; WADA banned in sport
- •Aromatizes to estradiol; converts to DHT via 5-alpha reductase; both metabolites matter clinically
- •Erythrocytosis (HCT above 54%) affects 5 to 25% of users and is the most common dose-limiting effect
Side-by-side
| Attribute | Alpha-GPC | Testosterone |
|---|---|---|
| Category | supplement | hormone |
| Also known as | L-Alpha glycerylphosphorylcholine, choline alfoscerate, GPC, alpha-glyceryl phosphorylcholine | TRT, testosterone replacement therapy, testosterone cypionate, testosterone enanthate, Androgel, Testim |
| Half-life (hr) ↗ | 4 | 192 |
| Typical dose (mg) ↗ | 600 | 150 |
| Dosing frequency | 1 to 3 times daily | weekly to twice-weekly (cypionate/enanthate IM or SC); daily (topical, oral); every 3 to 6 months (pellet) |
| Routes | oral | intramuscular, subcutaneous, topical, buccal, subcutaneous (pellet), oral |
| Onset (hr) | 1 | 24 |
| Peak (hr) | 2 | 72 |
| Molecular weight | 257.22 | 288.42 |
| Molecular formula | C8H20NO6P | C19H28O2 |
| Mechanism | Hydrolyzed to free choline and glycerophosphate after absorption; choline supports acetylcholine and phosphatidylcholine synthesis in CNS. | Androgen receptor agonist driving anabolic gene transcription in muscle, bone, brain, and androgen-sensitive tissue. Aromatized to estradiol and 5-alpha-reduced to DHT, both with distinct downstream effects. |
| Legal status | Dietary supplement (US); prescription medication in much of Europe | Schedule III controlled substance (US); WADA banned |
| WADA status | allowed | banned |
| DEA / Rx | OTC supplement | Schedule III |
| Pregnancy | Insufficient data; choline generally recommended in pregnancy | Category X; contraindicated in pregnancy (virilizing effect on female fetus) |
| CAS | 28319-77-9 | 58-22-0 |
| PubChem CID | 71920 | 6013 |
| Wikidata | Q411478 | Q150726 |
Safety profile
Alpha-GPC
Common side effects
- mild GI upset
- headache
- dizziness
- occasional insomnia with evening dosing
Contraindications
- established cardiovascular disease (TMAO concern)
- concurrent strong anticholinergic therapy
Interactions
- anticholinergic medications: partial mutual antagonism(minor)
- cholinesterase inhibitors (donepezil): additive cholinergic effect, basis for ASCOMALVA protocol(minor)
- scopolamine: partial counteraction of anticholinergic effect(minor)
Testosterone
Common side effects
- erythrocytosis
- acne
- oily skin
- fluid retention
- increased body hair
- fertility suppression
- injection-site reactions
Contraindications
- active prostate cancer
- active breast cancer
- untreated severe sleep apnea
- untreated severe BPH
- uncontrolled heart failure
- polycythemia at baseline
Interactions
- warfarin: may potentiate anticoagulant effect; monitor INR(moderate)
- insulin: may improve insulin sensitivity; monitor glucose in diabetics(moderate)
- 5-alpha reductase inhibitors (finasteride): blocks DHT conversion; reduces some androgen effects(moderate)
- aromatase inhibitors (anastrozole): lowers estradiol; risk of over-suppression(moderate)
Which Should You Take?
Alpha-GPC comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-B outcome catalogued. Testosterone is the right call when one of the conditionals below applies.
- → If your priority is focus or working memory, pick Alpha-GPC.
- → If your priority is athletic performance, pick Alpha-GPC.
- → If your priority is hormonal optimization, pick Testosterone.
- → If your priority is sexual function, pick Testosterone.
Edge case: If you want to avoid controlled substance, Alpha-GPC is the more accessible choice.
Default choice: Alpha-GPC. Lower friction to source, and broader goal coverage. Reach for Testosterone only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between Alpha-GPC and Testosterone?
Alpha-GPC and Testosterone differ in category (supplement vs hormone), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Alpha-GPC or Testosterone?
Alpha-GPC half-life is 4 hours; Testosterone half-life is 192 hours.
Can you stack Alpha-GPC with Testosterone?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper