Home Ingredients AlphaSize® (Alpha-GPC — Chemi Nutra)
CognitiveAthletic Performance

AlphaSize® (Alpha-GPC — Chemi Nutra)

Evidence Level
Strong
1 Clinical Trial
3 Documented Benefits
4/5 Evidence Score

AlphaSize® is a branded, high-purity alpha-GPC (alpha-glycerylphosphorylcholine), a choline compound that readily crosses into the brain and serves as a building block for the neurotransmitter acetylcholine. Made by Chemi Nutra, it is used both as a nootropic for memory and focus and as a sports ingredient for power output and growth hormone response. Alpha-GPC is one of the better-studied cholinergic compounds.

Studied Dose 300 to 600 mg per day for cognition; about 600 mg pre-exercise in sports studies.
Active Compound Alpha-glycerylphosphorylcholine (alpha-GPC), a highly bioavailable choline source and precursor to acetylcholine and membrane phospholipids.

Benefits

Memory and cognition

By supplying choline for acetylcholine synthesis, alpha-GPC supports memory and attention, and it has been studied in age-related cognitive decline both alone and alongside standard therapy.

Supported by Trial 1

Power and exercise output

Taken before training, alpha-GPC has been studied for improving lower-body power output and force, making it a popular pre-workout cognitive and performance ingredient.

Supported by Trial 1

Acetylcholine support

As a direct precursor, it helps maintain the acetylcholine signaling involved in learning, muscle activation, and focus.

Mechanism of action

1

Acetylcholine precursor

Alpha-GPC is cleaved to choline, which feeds acetylcholine production in the brain and at the neuromuscular junction, supporting cognition and muscle contraction.

2

Membrane phospholipid donor

Its glycerophosphate backbone contributes to phospholipid synthesis, supporting neuronal membrane integrity.

Clinical trials

1
Choline Alphoscerate and Cognition — Clinical Study
PubMed

Clinical comparison of choline alphoscerate (alpha-GPC) and citicoline in patients with cognitive impairment. (Sagaro and Amenta 2025, Frontiers in Neurology)

Adults with cognitive impairment.

Choline alphoscerate supported cognitive performance, consistent with a large body of work from this research group on alpha-GPC and acetylcholine-related cognition.

Side effects and drug interactions

Common Potential side effects

Generally well-tolerated — side effects are uncommon at normal doses.
Mild headache, heartburn, or dizziness is occasionally reported.
High doses may cause nervousness in sensitive people.

Important Drug interactions

Anticholinergic drugs — alpha-GPC opposes their action.
Scopolamine and similar agents — cholinergic ingredients may interact.
Tell your doctor if you take medication for memory or Alzheimer's disease.

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Frequently asked questions about AlphaSize® (Alpha-GPC — Chemi Nutra)

What is AlphaSize?

AlphaSize® is a branded, high-purity alpha-GPC (alpha-glycerylphosphorylcholine), a choline compound that readily crosses into the brain and serves as a building block for the neurotransmitter acetylcholine.

What is AlphaSize used for?

AlphaSize is researched primarily for Cognitive and Athletic Performance. By supplying choline for acetylcholine synthesis, alpha-GPC supports memory and attention, and it has been studied in age-related cognitive decline both alone and alongside standard therapy.

What is the recommended dosage of AlphaSize?

The clinically studied dose is 300 to 600 mg per day for cognition; about 600 mg pre-exercise in sports studies. Always follow the product label and check with a healthcare provider for personal advice.

Is AlphaSize safe, and does it have side effects?

For most healthy adults, AlphaSize is well tolerated at studied doses. Reported effects can include: Generally well-tolerated — side effects are uncommon at normal doses. Mild headache, heartburn, or dizziness is occasionally reported. It may also interact with some medications. AlphaSize is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does AlphaSize interact with any medications?

Possible interactions include: Anticholinergic drugs — alpha-GPC opposes their action. Scopolamine and similar agents — cholinergic ingredients may interact. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for AlphaSize?

NutraSmarts rates the evidence for AlphaSize as Strong (4 out of 5). It is backed by 1 clinical trial and 1 cited reference summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(1 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Sagaro GG, Amenta F. Comparison of the effects of choline alphoscerate and citicoline in patients with cognitive impairment. Front Neurol. 2025;16:1649661..PubMedUsed to support: Clinical evidence for alpha-GPC in cognition.