L-Norvaline

Non-proteinogenic amino acid that inhibits arginase enzyme, extending nitric oxide production and enhancing muscle pumps

Scientific name2-Aminopentanoic acid FormulaC5H11NO2 Molecular weight117.15 g/mol CAS6600-40-4

75 absorption score

5 safety / 10

35 USD per month

5 documented interactions

Check it against something

Evidence level C

L-Norvaline with:

75 out of 100

Works better together Compatible. Timing differs, so follow each supplement's own window.

Check it against your whole stack →

What it does

mechanism and evidence for each claim

Extended nitric oxide production

Prolongs nitric oxide effects by preventing arginine breakdown

Inhibits arginase enzyme that degrades arginine to ornithine Evidence C-grade 60-240 minutes

Sustained muscle pumps and vasodilation

Maintains muscle pumps for extended periods during and after training

Preserves arginine availability for continued nitric oxide synthesis Evidence C-grade 90-300 minutes

Enhanced effectiveness of NO precursors

Amplifies the effects of arginine and citrulline supplementation

Prevents enzymatic breakdown of arginine substrate Evidence C-grade Combined with NO precursors

Improved exercise performance

May enhance exercise capacity through sustained vasodilation

Maintained blood flow and nutrient delivery to muscles Evidence C-grade During exercise session

Synergistic pump enhancement

Works synergistically with other nitric oxide boosters

Prevents breakdown while other compounds increase production Evidence C-grade When combined with other NO boosters

Others take these for the same thing

Same goal, different mechanism — check any of them against this one

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Every pair we checked

12 combinations scored by the engine

L-Norvaline + Caffeine No documented interaction either way No known interaction 70

L-Norvaline + Creatine Monohydrate No documented interaction either way No known interaction 70

L-Norvaline + Vitamin D3 No documented interaction either way No known interaction 70

L-Norvaline + Calcium Carbonate No documented interaction either way No known interaction 70

L-Norvaline + Whey Protein No documented interaction either way No known interaction 70

L-Norvaline + Lactase No documented interaction either way No known interaction 70

L-Norvaline + Bovine Collagen No documented interaction either way No known interaction 70

L-Norvaline + DHA No documented interaction either way No known interaction 70

L-Norvaline + Turmeric No documented interaction either way No known interaction 70

L-Norvaline + Arginine AKG Enhanced and prolonged arginine effects Works better together 75

L-Norvaline + L-Citrulline Extended citrulline-derived arginine benefits Works better together 75

L-Norvaline + Beetroot Nitrates Complementary nitric oxide enhancement Works better together 75

Dosage

With other NO boosters

Daily100-300mg

Pump extension100-200mg with arginine/citrulline

Pre workout addition50-150mg as part of formula

Experimental use200-300mg daily maximum

Synergistic stacking100-200mg with established NO boosters

When to expect it

First Effects45-90 minutes when combined with NO precursors

Peak Benefits90-240 minutes for maximum pump extension

Deficiency DevelopmentNot applicable - non-essential amino acid

Toxicity OnsetUnknown - limited safety data

How to measure it

$300-500

MarkerArginase activity, arginine levels (research only)

OptimalNo established clinical ranges

Deficient belowNot applicable - non-essential compound

FrequencyResearch purposes only - monitor subjective pump effects

What actually reaches you

The label counts the carrier, your body does not

Absorption High 75 of 100 · absorbs well relative to other forms

Delivered daily 150 mg

Cost per 100 mg delivered $0.78 comparative — uses the absorption score, not a measured percentage

Works better with

3 documented

L Arginine

Enhanced and prolonged arginine effects

Norvaline prevents arginine breakdown by arginase · level C

L Citrulline

Extended citrulline-derived arginine benefits

Preserves arginine produced from citrulline conversion · level C

Nitrates

Complementary nitric oxide enhancement

Different pathways for NO production working together · level C

What not to take with L-Norvaline

2 documented

Ornithine High Doses

High ornithine may compete with norvaline effects

Ornithine is product of arginase that norvaline inhibits · theoretical significance

Arginase Enhancers

Compounds that upregulate arginase may oppose norvaline

Counteracts norvaline's enzyme inhibition · theoretical significance

Medication interactions

Discuss these with a pharmacist before combining

liver-metabolized-medications Unknown

Potential interaction with hepatically metabolized drugs

What to do: Use caution with liver-processed medications

blood-pressure-medications Minor

May enhance hypotensive effects indirectly

What to do: Monitor blood pressure if using NO enhancers

Available forms

bioavailability compared

L-Norvaline (Pure Amino Acid) 75

L-Norvaline (Pure Amino Acid): Extends NO effects, Synergistic benefits, Small doses needed, Unique mechanism

Food sources

before you supplement

Not found in significant amounts in food Trace amounts in some proteins · N/A

Supplement form required Therapeutic doses only from supplements · N/A

Pre-workout formulas 50-200mg in advanced formulas · 75

L-Norvaline supplements 100-500mg per serving · 75

Too little

deficiency signs

Not applicable (non-essential, non-proteinogenic amino acid):
Potential benefits addressed by norvaline:
Short-lived nitric oxide effects
Rapid pump decline during training
Suboptimal effectiveness of NO precursors
Poor sustainability of vasodilation

Too much

toxicity signs

Limited safety data - potential concerns:
Unknown long-term effects
Possible liver metabolism disruption
Theoretical hepatotoxicity at high doses
Individual sensitivity variations
Interaction potential with other supplements

Who benefits most

advanced-pump-enthusiasts

Seeks maximum pump duration and intensity

100-200mg combined with arginine/citrulline

pre-workout-formula-users

Often included in advanced pre-workout supplements

50-150mg as part of comprehensive formula

bodybuilders-physique-competitors

Enhanced vascularity and pump for training and competition

100-200mg with other NO boosters

supplement-experimenters

Interested in cutting-edge supplements with unique mechanisms

100-300mg daily as tolerated

stack-optimizers

Wants to maximize effectiveness of existing NO supplements

100-200mg with arginine/citrulline stack

Where to buy it

compare forms first

Look for L-Norvaline at 100-300mg per serving. The form that matters here is L-Norvaline (Pure Amino Acid).

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How it works

Competitive inhibitor of arginase enzyme
Prevents conversion of arginine to ornithine and urea
Maintains arginine availability for nitric oxide synthase
Extends half-life of arginine in circulation
Does not directly produce nitric oxide itself
Works synergistically with arginine and citrulline

Key findings

what the evidence supports

Limited human research but promising mechanism for pump enhancement
Effective arginase inhibitor in laboratory studies
Safety profile not well established in humans
Best used in combination with established NO precursors

Sources: NIH Examine.com · data reviewed 2026-08-01

Compiled by Denis, who maintains this database and holds no medical qualification — every figure here is sourced or derived, never asserted. How we calculate it →

Common questions

What are the benefits of L-Norvaline?

Documented effects: Extended nitric oxide production; Sustained muscle pumps and vasodilation; Enhanced effectiveness of NO precursors; Improved exercise performance. Prolongs nitric oxide effects by preventing arginine breakdown

How much L-Norvaline should you take per day?

The common daily range is 100-300mg. By goal — pump extension: 100-200mg with arginine/citrulline; pre workout addition: 50-150mg as part of formula; experimental use: 200-300mg daily maximum; synergistic stacking: 100-200mg with established NO boosters.

When is the best time to take L-Norvaline?

With other NO boosters. First effects are typically reported within 45-90 minutes when combined with NO precursors.

What are the side effects of L-Norvaline?

At excessive doses: Limited safety data - potential concerns:, Unknown long-term effects, Possible liver metabolism disruption, Theoretical hepatotoxicity at high doses, Individual sensitivity variations. Safety rating at normal doses is 5 out of 10.

What should you not take with L-Norvaline?

Separate it from Ornithine High Doses, Arginase Enhancers by two to four hours. High ornithine may compete with norvaline effects

Does L-Norvaline interact with medications?

Documented interactions with liver-metabolized-medications, blood-pressure-medications. Discuss these with a pharmacist before combining.

How do you know if you need L-Norvaline?

The marker is Arginase activity, arginine levels (research only), optimal range No established clinical ranges. Common deficiency signs: Not applicable (non-essential, non-proteinogenic amino acid):, Potential benefits addressed by norvaline:, Short-lived nitric oxide effects, Rapid pump decline during training.

Taken for

43 Performance

Caffeine · Creatine Monohydrate · Whey Protein