Quick Comparison

ALCARPQQ
Half-Life4-5 hours3-5 hours (plasma), but effects on mitochondrial biogenesis persist
Typical DosageStandard: 500-2000 mg daily in 1-2 doses. For cognitive support: 1000-2000 mg daily. For neuropathy: 1500-3000 mg daily. Take in the morning — may be mildly stimulating.Standard: 10-20 mg daily. Often combined with CoQ10 (100-300 mg) for synergistic mitochondrial support. Higher doses (40 mg) are used in some research settings.
AdministrationOral (capsules, powder). Well-absorbed on an empty stomach.Oral (capsules, softgels). Best absorbed on an empty stomach. BioPQQ is the most studied branded form.
Research Papers9 papers10 papers
Categories

Mechanism of Action

ALCAR

ALCAR crosses the blood-brain barrier via the organic cation transporter (OCTN2) more effectively than L-carnitine. In neurons, it is hydrolyzed by carnitine acetyltransferase to donate its acetyl group to coenzyme A, forming acetyl-CoA—which can then be used for acetylcholine synthesis via choline acetyltransferase, effectively providing raw material for the memory neurotransmitter. ALCAR also transports long-chain fatty acids across the inner mitochondrial membrane via the carnitine palmitoyltransferase system for beta-oxidation and ATP production. ALCAR activates nerve growth factor (NGF) signaling, possibly through modulation of NGF receptor (TrkA) expression or downstream MAPK/ERK pathways. It has antioxidant properties, reducing lipid peroxidation in mitochondrial membranes and scavenging free radicals. These mechanisms support cognitive function and neuroprotection.

PQQ

PQQ activates PGC-1alpha (peroxisome proliferator-activated receptor gamma coactivator 1-alpha), the master transcriptional regulator of mitochondrial biogenesis. PGC-1alpha coactivates NRF-1 and NRF-2, which drive expression of mitochondrial transcription factor A (TFAM) and nuclear-encoded mitochondrial genes—the process of creating new mitochondria in existing cells. This is unique among commercially available supplements. PQQ also provides antioxidant protection through extremely efficient redox cycling at the N5 position; it can undergo thousands of oxidation-reduction cycles before being exhausted, estimated at 5,000x the efficiency of vitamin C. PQQ activates the CREB (cAMP response element-binding protein) signaling pathway and may enhance NGF signaling, supporting BDNF expression, synaptic plasticity, and neuronal survival.

Risks & Safety

ALCAR

Common

Nausea, fishy body odor, restlessness, gastrointestinal discomfort.

Serious

May increase agitation in Alzheimer's patients. TMAO production may be a cardiovascular concern with chronic high doses.

Rare

Seizures in susceptible individuals, increased thyroid activity.

PQQ

Common

Very few — PQQ has an excellent safety profile at standard doses. Mild headache, fatigue initially.

Serious

No serious adverse effects documented.

Rare

Insomnia, irritability.

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