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Ingredients/Amino acid/Pyroglutamic Acid (Pidolic Acid)

Pyroglutamic Acid (Pidolic Acid).

Strength pending.The research strength is not set yet.

It's the ring form of glutamate that cycles through the pathway your body uses to move amino acids into cells. As a pidolate salt it also carries minerals in solution.

250 to 500mgDaily amount

Reviewed March 2026

PAAmino acid
Pyroglutamic Acid (Pidolic Acid)IngredientMD
Category
Amino acid

What Pyroglutamic Acid (Pidolic Acid) is, and what it does.

Does it work
Suits people already taking a pidolate mineral salt, and anyone curious about glutamate handling. If you want a mineral in a liquid or sachet, this is the carrier that dissolves easily.
How much to take
Start with 250 to 500mg a day, which is the daily maintenance band on record. The 1,000mg used in studies is a research condition rather than a daily target.
Time to feel it
There's no onset you would time with a stopwatch. Its work shows up in amino acid and glutathione pathway chemistry rather than in a sensation.
The first dose
Day one is quiet. The molecule joins a cycle already running in every cell, so the change sits in pathway chemistry rather than in anything you would sense.
With regular use
Weeks of daily use keep a pidolate mineral topped up and feed the glutamate side of the gamma-glutamyl cycle. That shows up on a lab panel, not in mood.
How well tolerated
Well tolerated at supplement amounts, usually taken as a mineral salt. If you have kidney concerns or already take other mineral supplements, check with your clinician first.
How it feels
Most people describe no sensation at all. It behaves like a carrier and a pathway intermediate, so the change is in chemistry rather than in how the day feels.
The overlooked benefit
Its sodium salt is part of skin's own natural moisturising factor, which is why the same molecule turns up as a humectant in topical formulas.

250 to 500mg a day is where Pyroglutamic Acid (Pidolic Acid) works.

How much to take a dayLimited data
250 to 500mg
Daily maintenanceThe everyday amount, and where most daily supplements sit. This is the one you take month after month.
1,000mgClinical territory. Trials run high on purpose, for a set number of weeks, against one measured outcome. Impressive to hit, and not what a daily product is for.
Above 1,500mgPast what the research covers. More capsules rather than more effect.
MORE EFFECT ↑0500mg1,000mg plateauDAILY DOSE →
The shaded band is where the dosing trials landed.

Source: Grioli et al., 1990; limited clinical literature

The proof, claim by claim.

These words describe the research, not the molecule's worth. Research strength is how much work stands behind one claim, and it is never a product score.

Pyroglutamic Acid (Pidolic Acid) has emerging evidence. Based on 5+ studies.

  • amino acid transport through the gamma-glutamyl cycleNarrative review
  • marker of glutathione synthesis fluxNarrative review
  • mineral delivery as a soluble pidolate saltRandomised trial
  • water binding at the skin surfaceIn vitro study
PubMedCochraneClinicalTrials.govNIH ODSSUPP.AILabs test. IngredientMD verifies.PubMedCochraneClinicalTrials.govNIH ODSSUPP.AILabs test. IngredientMD verifies.

Questions people ask about Pyroglutamic Acid (Pidolic Acid).

When should I take it?
Timing matters less than consistency. Pick a time that works for you and take it daily.
Can I take it with other supplements?
Usually fine. The main thing to watch is not doubling up on the same ingredient from different products. If you're on prescription meds, check with your pharmacist first.
Any side effects to watch for?
Most people tolerate it well at recommended doses. GI upset is the most common complaint with any supplement. Start with a lower dose and work up. If something feels off, stop and reassess.
Who benefits most from this?
People who've already covered the basics (diet, sleep, exercise) and want to fine-tune. It's not essential, but could be worthwhile for the right person.
Pairs well with17 on file

Why these belong in the same formula. Each row says what the basis is, from settled biochemistry through to a trial that measured the pair.

Pyroglutamate is the cyclised form of glutamate and interconverts with the glutamine and glutamate pool through the gamma-glutamyl cycle. They occupy the same nitrogen pathway.

Pyroglutamate is generated when the gamma-glutamyl cycle turns over glutathione, and 5-oxoprolinase returns it to glutamate for resynthesis. The two sit on opposite ends of the same loop.

Glycine is released and reincorporated as the gamma-glutamyl cycle recycles glutathione, the same cycle that produces pyroglutamate.

Arginine pyroglutamate is a long-used salt in which pyroglutamic acid is the counter-ion that improves arginine's solubility and absorption profile.

Sodium pyroglutamate is one of the components of skin's natural moisturising factor and holds water in the outer layer, the same job hyaluronic acid does at a larger molecular size.

Pyroglutamic Acid (Pidolic Acid) + L-cysteineThe gamma-glutamyl cycle, in which pyroglutamate is an intermediate, is the route that supplies cysteine for glutathione synthesis.

Pyroglutamate is formed when gamma-glutamyl cyclotransferase releases an amino acid from its gamma-glutamyl carrier, and cysteine is the amino acid that route most matters for. Cysteine availability is the rate-limiting input to glutathione synthesis. The two sit on the same cycle at different points.

Pyroglutamic Acid (Pidolic Acid) + NACN-acetylcysteine supplies cysteine to the same glutathione synthesis step the gamma-glutamyl cycle serves.

NAC is deacetylated to cysteine, which glutamate cysteine ligase then joins to glutamate. Rising pyroglutamate is a recognised laboratory sign that this cycle is running with insufficient cysteine relative to the gamma-glutamyl flux. The relationship is a direct one within a single well-mapped cycle.

Pyroglutamic Acid (Pidolic Acid) + L-methionineThe transsulfuration pathway converts methionine sulfur into cysteine, feeding the same cycle.

Methionine passes through homocysteine and cystathionine to yield cysteine, which is the input the gamma-glutamyl cycle consumes. Adequate methionine and adequate B6 for the cystathionase step therefore both affect that supply. This is settled sulfur amino acid biochemistry.

Pyroglutamic Acid (Pidolic Acid) + Alpha-lipoic acidEstablished redox recycling of glutathione, the end product of the cycle pyroglutamate belongs to.

Dihydrolipoic acid reduces oxidised glutathione back to its active form, which lowers the demand for new synthesis through the gamma-glutamyl cycle. Pyroglutamate sits inside that synthesis loop. The two act on supply and on recycling respectively.

Pyroglutamic Acid (Pidolic Acid) + MagnesiumMagnesium pidolate is an established salt form using pyroglutamate as the counter-ion.

Pidolate is the anion in magnesium pidolate, a highly water-soluble magnesium form used in liquid and sachet products. The pyroglutamate here works as a solubilising counter-ion rather than as an independent active. Anyone reading a label should know both halves of the salt contribute weight.

Pyroglutamic Acid (Pidolic Acid) + ZincZinc pidolate is an established salt form using the same counter-ion.

Zinc pidolate pairs zinc with pyroglutamate to give a soluble, comparatively low-astringency zinc form used in liquids and topicals. The counter-ion determines solubility and taste rather than what the zinc does. Elemental zinc per gram of salt differs from that of other zinc forms.

Pyroglutamic Acid (Pidolic Acid) + CalciumCalcium pidolate is an established soluble calcium salt.

Calcium pidolate dissolves far more readily than calcium carbonate, which suits liquid formats where a suspension is unwanted. The pyroglutamate is again the counter-ion. It contributes to the salt weight without contributing calcium.

Pyroglutamic Acid (Pidolic Acid) + PotassiumPotassium pidolate is used where a soluble, low-chloride potassium source is wanted.

Potassium pidolate provides potassium without the chloride load of potassium chloride and without the taste burden that comes with it. The pidolate anion is metabolised through the gamma-glutamyl cycle rather than excreted unchanged. Format choice is what usually drives the selection.

Pyroglutamic Acid (Pidolic Acid) + SodiumSodium PCA, the sodium salt of pyroglutamic acid, is a standard humectant in the natural moisturising factor of skin.

Sodium pyrrolidone carboxylate is one of the main water-binding components the skin makes for itself when filaggrin is broken down in the outer layer. Cosmetic formulations use the same molecule as a humectant for that reason. The role here is water binding, not electrolyte supply.

Pyroglutamic Acid (Pidolic Acid) + CeramidesBoth are components of the skin barrier system, one as the lipid matrix and one as a water-binding factor.

Ceramides form the lipid layers between the outermost skin cells, while pyroglutamate as sodium PCA holds water inside those cells. Barrier function depends on both the lipid seal and the water-binding capacity behind it. The pairing is standard topical formulation architecture.

Pyroglutamic Acid (Pidolic Acid) + SqualaneOcclusive lipid paired with a humectant in standard topical formulation practice.

Squalane slows water loss from the surface while sodium PCA draws and holds water in the outer layer. Humectants perform poorly in dry air without something to reduce evaporation. Combining the two is formulation convention rather than a measured interaction.

Pyroglutamic Acid (Pidolic Acid) + Vitamin B6 (pyridoxine)Pyridoxal 5-phosphate is the cofactor for cystathionine gamma-lyase, the step that releases cysteine for the cycle.

Cysteine reaching the gamma-glutamyl cycle from methionine has to pass through two B6-dependent transsulfuration enzymes. Low B6 constrains that supply regardless of methionine intake. It is a cofactor dependency one step upstream of where pyroglutamate sits.

Who should be cautious

Nothing specific on file for Pyroglutamic Acid (Pidolic Acid). Match the label to the daily amount above, and tell your doctor what you take.

Not medical advice. Show the label to your pharmacist.

What Pyroglutamic Acid (Pidolic Acid) actually does.

Established

Pyroglutamic acid, also called 5-oxoproline or pidolic acid, is the cyclic lactam formed when the amino group of glutamate condenses with its own side-chain carboxyl and loses water.

Established

It is an intermediate of the gamma-glutamyl cycle: gamma-glutamyl cyclotransferase releases the transported amino acid and leaves 5-oxoproline behind, which 5-oxoprolinase then reopens to glutamate at the cost of one ATP.

Established

Because 5-oxoproline accumulates when glutathione synthesis is running short of cysteine, its concentration is used clinically as a marker of that imbalance; it is a marker of pathway flux, not an outcome in itself.

Established

Many proteins and peptides carry a pyroglutamate residue at their N-terminus, formed spontaneously or enzymatically from glutamine or glutamate, which blocks standard N-terminal sequencing and slows degradation by aminopeptidases.

More than one route, 6 steps on record

Where Pyroglutamic Acid (Pidolic Acid) comes from.

The starting material is glutamic acid, made by feeding sugar to bacteria in a fermenter, which is the same process behind most amino acids sold in bulk. Heating it makes the molecule fold into a ring and lose a water molecule, and that ring is pyroglutamic acid. It is then cleaned up and usually paired with magnesium, zinc, calcium or another partner to make a salt that dissolves easily in water.

The same molecule is reached more than one way. Which route a given product used is a manufacturing choice, and the finished compound is the same either way.

Starts as
L-glutamic acid from sugar fermentation

L-glutamic acid is produced industrially by fermenting a sugar feedstock such as cane molasses or starch hydrolysate with Corynebacterium glutamicum, one of the largest-volume amino acid fermentations there is.

Converted by
Thermal cyclisation to the lactam

Glutamic acid is heated under controlled conditions so the amino group condenses with the side-chain carboxyl and water is eliminated, closing the five-membered ring. Preserving the L configuration is what the temperature and pH control is for.

Purified by
Crystallisation from solution

The cyclised product is crystallised away from unreacted glutamic acid, glutamine and any racemised material.

Standardised to
Assay for optical purity and residual glutamate

Lots are checked for optical rotation, since the D form does not participate in the gamma-glutamyl cycle, and for residual free glutamic acid.

Converted by
Salt formation with a mineral or amino acid base

The purified acid is neutralised with magnesium, zinc, calcium, potassium, sodium hydroxide or arginine to a defined stoichiometry, which is how the pidolate salts are made.

Ends up as
Dried powder or concentrated solution

The salt is spray-dried or crystallised for powder formats, or held as a concentrated aqueous solution for liquid manufacture, with moisture controlled because the material is hygroscopic.

Getting Pyroglutamic Acid (Pidolic Acid) from food.

The whole-food sources on file. A supplement closes the gap, it does not replace dinner.

Aged hard cheeseTomato juiceCane molasses

A gram-for-gram figure (how much of each you would eat to match a dose) will appear here once it is sourced and reviewed. This page will not print a number it cannot cite.

The forms it comes in.

Pidolic acidThe unneutralised cyclic acid, moderately water-soluble and mildly acidic, in the naturally occurring L configuration.Fits Manufacturing intermediate for pidolate salts and applications where no added mineral or amino acid is wanted.Trade-off The acidity limits how much can go into an unbuffered liquid, and the free acid attracts moisture in storage.Active and formulation aid
Sodium PCAThe sodium salt, extremely water-soluble and strongly water-binding, identical to a component the skin makes itself.Fits Topical humectant systems and any aqueous format where a neutral pH and high solubility are needed.Trade-off Its water-binding strength cuts both ways in low humidity, so it is usually paired with an occlusive lipid, and it adds sodium.Active and formulation aid
Magnesium pidolateMagnesium paired with two pidolate anions, giving a magnesium form with very high water solubility.Fits Liquids, sachets and ampoules where a magnesium salt has to dissolve fully and clearly.Trade-off Elemental magnesium per gram of salt is low because the two pidolate anions carry a lot of weight, so dose volumes are larger.
Zinc pidolateZinc paired with pidolate, soluble and comparatively low in astringency for a zinc salt.Fits Liquid oral formats and topical preparations where zinc taste and skin feel are limiting.Trade-off Elemental zinc per gram of salt is lower than for zinc oxide or zinc sulfate, and it costs more per unit of zinc.
Calcium pidolateCalcium paired with two pidolate anions, far more soluble in water than calcium carbonate.Fits Clear liquid and effervescent calcium products where a suspension would be unacceptable.Trade-off Carries a low elemental calcium percentage, so it cannot deliver a large calcium dose in a small volume.
Arginine pidolateAn amino acid salt in which both the cation and the anion are metabolisable amino acid derivatives.Fits Formulas that want no mineral counter-ion at all and can make use of the arginine.Trade-off Both halves of the salt are biologically active, so the arginine contribution has to be counted in the formula rather than ignored.Active and formulation aid

FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. This information is for educational purposes only and is not intended to diagnose, treat, cure, or prevent any disease. Consult your healthcare provider before starting any supplement regimen.