Noradrenaline bitartrate
[CAS# 69815-49-2]

Identification

• Classification: API >> Circulatory system medication
• Name: Noradrenaline bitartrate
• Synonyms: L-4-(2-Amino-1-hydroxyethyl)-1,2-benzenediol bitartrate
• Molecular Formula: C₈H₁₁NO₃^.C₄H₆O₆^.H₂O
• Molecular Weight: 337.28
• CAS Registry Number: 69815-49-2
• EC Number: 640-994-9
• SMILES: C1=CC(=C(C=C1C(CN)O)O)O.C(C(C(=O)O)O)(C(=O)O)O.O

Properties

• Melting point: 100-106 ºC (Expl.)
• Solubility: DMSO: 67 mg/mL, Water: <1 mg/mL, Ethanol 7 mg/mL (Expl.)
• Alpha: -46 º (c=0.5, HCl) (Expl.)

Safety Data

• Hazard Symbols: GHS07 Warning
• Hazard Statements: H302
• Precautionary Statements: P264-P270-P301+P317-P330-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	1	H300
Acute toxicity	Acute Tox.	2	H310
Acute toxicity	Acute Tox.	2	H330
Reproductive toxicity	Repr.	1B	H360

Discovory and Applicatios

Noradrenaline bitartrate, also known as norepinephrine bitartrate, is the bitartrate salt form of noradrenaline, a naturally occurring catecholamine and neurotransmitter. Chemically, it consists of noradrenaline combined with the bitartrate anion derived from tartaric acid. The molecular formula of noradrenaline bitartrate is C₈H₁₂NO₃·C₄H₆O₆, reflecting the combination of noradrenaline and the bitartrate moiety.

Noradrenaline is a key hormone and neurotransmitter involved in the sympathetic nervous system, mediating physiological responses such as vasoconstriction, increased heart rate, and blood pressure elevation. It acts primarily on alpha-adrenergic and beta-adrenergic receptors, with high affinity for alpha-1 and beta-1 receptors, resulting in vasoconstrictive and cardiac stimulant effects.

The bitartrate salt form improves the stability and solubility of noradrenaline for pharmaceutical formulations, facilitating its use in intravenous and other parenteral preparations. Noradrenaline bitartrate is commonly administered in emergency and critical care settings to manage hypotension, shock, and cardiac arrest by restoring vascular tone and cardiac output.

Pharmacologically, noradrenaline stimulates alpha-1 adrenergic receptors on vascular smooth muscle cells, causing vasoconstriction and thereby increasing systemic vascular resistance and blood pressure. Activation of beta-1 receptors in the heart enhances myocardial contractility and heart rate, contributing to improved cardiac output.

Due to its potent vasopressor activity, noradrenaline bitartrate requires careful dosing and monitoring to avoid excessive hypertension, arrhythmias, or tissue ischemia. It is typically administered by continuous intravenous infusion under controlled clinical settings.

Pharmacokinetics of noradrenaline involve rapid metabolism by enzymes such as monoamine oxidase (MAO) and catechol-O-methyltransferase (COMT), resulting in a short plasma half-life. Its metabolites are primarily excreted via the kidneys.

In summary, noradrenaline bitartrate is a clinically important salt form of noradrenaline used as a potent vasopressor agent in acute medical care. Its chemical stability, solubility, and pharmacodynamic properties make it essential for managing hypotensive emergencies.

References

1979. Evaluation of plasma norepinephrine as an index of sympathetic neuron function in the conscious, unrestrained rat. Life Sciences, 24(22).
DOI: 10.1016/0024-3205(79)90080-8

2024. Comparison of vasopressors for management of hypotension in high-risk caesarean section under neuraxial anesthesia: a systematic review and network meta-analysis. BMC Anesthesiology, 24(1).
DOI: 10.1186/s12871-024-02819-9

2025. Adrenal epinephrine facilitates erythropoietin gene activation by hypoxia through β2 adrenergic receptor interaction with Hif-2α. American Journal of Physiology. Regulatory, Integrative and Comparative Physiology, 328(1).
DOI: 10.1152/ajpregu.00201.2024