| Names | |
|---|---|
| IUPAC name
L-aspartic acid potassium salt | |
| Other names
L-Aspartic acid, potassium salt (1:1); Aspartic acid, monopotassium salt, L-; L-Aspartic acid, monopotassium salt; Monopotassium aspartate; Potassium hydrogen aspartate; Aspartic acid monopotassium salt; Aspara K | |
| Identifiers | |
3D model (JSmol) |
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| ChemSpider | |
| DrugBank | |
| ECHA InfoCard | 100.012.934 |
| EC Number |
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| KEGG | |
PubChem CID |
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| UNII | |
CompTox Dashboard (EPA) |
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| Properties | |
| C4H6KNO4 | |
| Molar mass | 171.193 g·mol−1 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Potassium aspartate is a potassium salt of L-aspartic acid, an amino acid, with the chemical formula KO2CCH(NH2)CH2CO2H·H2O.
The compound is used as a dietary supplement to treat low potassium levels (hypokalemia) and high blood ammonia (hyperammonemia), and is under investigation as an adjunctive treatment for hypertension.
Potassium aspartate is also employed in cosmetics as a buffering agent.[citation needed]
Potassium aspartate is also used in research settings for electrophysiological studies, as a chloride substitute in patch-clamp pipette solutions.
Potassium aspartate is a white powder that is water-soluble. It consists of potassium cations (K+) bound to aspartate anion. The monohydrate form has a molecular weight of 171.19 g/mol. In supplements, each 450 mg capsule typically provides 99 mg of elemental potassium, equivalent to approximately 2.53 mEq. Potassium aspartate hemihydrate (C4H6KNO4·½H2O) has a molar mass of 180.20 g/mol and contains approximately 21.7% potassium by mass, or about 217 mg of elemental potassium per gram. For example, the 166.3 mg of potassium aspartate hemihydrate in one Panangin tablet (corresponding to 158 mg of the anhydrous salt) supplies 36.2 mg of K+. In research, potassium aspartate is used in electrophysiological studies, such as in pipette solutions for voltage-clamp experiments, to maintain intracellular potassium levels and support ionic currents (for example, Ca2+-activated K+ currents in gonadotropes).

Potassium aspartate is not approved for use as a chemical in its own right (but may be approved as a component in a product covered by a group standard) in the United States or European Union or New Zealand or Australia, for treating any medical condition, but is studied as an alternative to potassium chloride to treat high blood pressure (hypertension): potassium chloride reduces blood pressure, with a more pronounced effect in patients with hypertension, averaging a reduction of 8.2 mm Hg systolic and 4.5 mm Hg diastolic; potassium aspartate may have a greater impact on lowering blood pressure at lower doses. Increasing intake of potassium-rich foods such as bananas, grapefruit, dried beans, peas, broccoli, spinach, pumpkins and squash is preferable, and potassium aspartate is studied as a potential adjunctive treatment for hypertension. Potassium aspartate is sometimes marketed in a mixture with magnesium aspartate.
Potassium aspartate is used as a dietary supplement to treat or prevent hypokalemia (low blood potassium levels), which can cause muscle weakness, cramps, fatigue and irregular heart rhythms. Hypokalemia is typically due to excessive potassium loss (for example, via urine or intestines) rather than dietary deficiency, often triggered by diuretics, vomiting or diarrhea. In cases of metabolic acidosis, potassium aspartate may be preferred over potassium chloride because of its alkalinizing properties. Doses of 1.5–3 g (20–33 mEq) per day are recommended when dietary sources such as bananas and spinach are insufficient, with serum potassium levels monitored to avoid hyperkalemia.
Potassium aspartate is under investigation as an alternative to potassium chloride for managing hypertension (high blood pressure). Victoria Maizes, in the hypertension chapter of Integrative Medicine (second edition, 2007), reports a meta-analysis of 19 trials in which potassium chloride reduced blood pressure by an average of 8.2 mm Hg systolic and 4.5 mm Hg diastolic in hypertensive patients, and cites later work suggesting that potassium aspartate may achieve similar effects at lower doses. The mechanism involves the role of potassium in balancing sodium levels, relaxing vascular smooth muscle and reducing blood vessel stiffness. Clinical evidence for the superiority of potassium aspartate is limited.
Studies from the 1960s explored oral potassium aspartate combined with magnesium aspartate (1 g each) for chronic fatigue, reporting symptom relief in 75%–91% of nearly 3,000 patients after 4–10 days of treatment, compared with 9%–26% with placebo. These findings lack modern replication, and potassium aspartate is not approved for fatigue treatment because the evidence is insufficient.
Potassium aspartate is used in some settings to treat hyperammonemia (high blood ammonia), particularly in liver cirrhosis, by enhancing ammonia detoxification pathways. This application is typically intravenous and administered by healthcare professionals.
Potassium aspartate is used in cosmetics and personal care products, such as baby products, bath products and hair care, as a buffering agent to stabilize pH and enhance product texture. The Cosmetic Ingredient Review Expert Panel has deemed it safe for topical use, citing its low hazard profile and established safety as a food additive. The Food and Drug Administration permits its use in over-the-counter products.
In electrophysiological research, potassium aspartate is a component of pipette solutions for patch-clamp studies, maintaining intracellular potassium concentrations. For example, a solution with 120 mM potassium aspartate is used to study gonadotrope responses to gonadotropin-releasing hormone (GnRH), supporting oscillatory Ca2+-activated K+ currents.[citation needed]