Adenosine A₁ receptor – binding Ki = 2.8 × 10⁻⁷ M (0.28 μM) [1]
Adrenergic α₂ receptor – binding Ki = 6.1 × 10⁻⁶ M (6.1 μM) [1]
Dopamine D₂ receptor – binding Ki = 1.5 × 10⁻⁶ M (1.5 μM) [1]
Muscarinic M₂ receptor – binding Ki = 1.9 × 10⁻⁶ M (1.9 μM) [1]

In vitro activity :Flavoxate is an anticholinergic agent that binds and inhibits muscarinic receptors, thereby suppressing the micturition reflex and increases urinary bladder capacity by modifying the micturition center in the brain stem.As an anticholinergic,Flavoxatehas the potential to be used in various urinary syndromes and as an antispasmodic. Flavoxate (3 mg/kg, i.v.) completely abolished rhythmic bladder contractions in vehicle-pretreated rats, but not in PTX-pretreated rats. These findings suggest that signal transduction via Gi-coupled receptors is involved, at least in part, in the inhibition of the micturition reflex by flavoxate in rats.Cell Assay:Flavoxate (>10 μM) suppresses carbachol-induced contractions in isolated rat detrusor strips with pD value of 4.55. Flavoxate (>10 μM) suppresses Ca2+-induced contractions in isolated rat detrusor strips with pIC50 value of 4.92. Flavoxate (0.01 μM -10 μM) inhibits CAMP formation in a concentration-dependent manner in membranes from the rat striatum and cerebral cortex, an action which is completely abolished by pretreating the membranes with pertussis toxin (PTX).

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Flavoxate (10⁻⁸ M to 10⁻⁵ M) concentration‑dependently inhibited cAMP formation in rat striatal membranes, with 38% inhibition at 10⁻⁵ M. This effect was completely abolished by pretreating membranes with pertussis toxin (PTX, 10 μg/ml, 1 h at 30 °C). [1]
Flavoxate (10⁻⁸ M to 10⁻⁵ M) also inhibited cAMP formation in rat cerebral cortex membranes, though less markedly than in striatum. [1]
The inhibitory effect of Flavoxate (10⁻⁶ M) on cAMP formation was not significantly blocked by individual antagonists DPCPX (adenosine A₁ antagonist, 10⁻⁶ M), sulpiride (dopamine D₂ antagonist, 10⁻⁵ M), or yohimbine (α₂ antagonist, 10⁻⁶ M), but was completely antagonized by combined treatment with any two of these three antagonists. Atropine (10⁻⁷ M) had no effect. [1]
Radioligand binding assays showed that Flavoxate (10⁻⁸ M to 10⁻⁴ M) had affinity for adenosine A₁ (Ki = 2.8 × 10⁻⁷ M), adrenergic α₂ (Ki = 6.1 × 10⁻⁶ M), dopamine D₂ (Ki = 1.5 × 10⁻⁶ M), and muscarinic M₂ (Ki = 1.9 × 10⁻⁶ M) receptors, but negligible affinity for β, D₁, A₂, GABAA, GABAB, and opioid receptors. [1]

Flavoxate (10mg/kg) suppresses both the an initial, rapidly rising phasic contraction (phase 1) and the tonic contraction (phase 2) contractions to the same extent in rats. Flavoxate (10mg/kg) abolishes the bladder contractions without causing any change in the amplitude of the contractions in rats. Flavoxate (3 mg/kg) abolishes the efferent neural activity and the associated bladder contractions for about 10 minutes without changing the baseline vesical pressure in rats. ICV-injected (50 to 200 μg/rat) or IT-injected (100 to 200 μg/rat) Flavoxate abolishes rhythmic bladder contractions during and after injection for five to 15 minutes in a dose-dependent manner in rats [2]. Flavoxate (3 mg/kg, i.v.) abolishes rhythmic bladder contractions and the maximal intervals of voiding contractions is 7.20 min
In vehicle‑pretreated rats, intravenous Flavoxate (3 mg/kg) markedly suppressed isovolumetric rhythmic bladder contractions, increasing the maximal inter‑contraction interval from 1.07 ± 0.08 min to 7.20 ± 1.10 min (p < 0.01). In rats pretreated intracerebroventricularly with pertussis toxin (PTX, 1 μg/5 μl, 4 days earlier), Flavoxate failed to inhibit rhythmic contractions (interval increased from 1.10 ± 0.09 min to only 1.77 ± 0.14 min). Contraction amplitudes were unaffected by PTX pretreatment. [1]
In striatal membranes from PTX‑pretreated rats, Flavoxate (10⁻⁶ M), PIA (A₁ agonist, 10⁻⁷ M), quinpirole (D₂ agonist, 10⁻⁶ M), and clonidine (α₂ agonist, 10⁻⁷ M) no longer inhibited cAMP formation, whereas in vehicle‑pretreated rats they did. In bladder membranes, Flavoxate inhibited cAMP formation regardless of PTX pretreatment. [1]

cAMP assay: Rat striatal or cerebral cortex membranes were prepared in TED buffer (10 mM Tris‑HCl pH 7.4, 1 mM EDTA, 10 mM MgCl₂, 1 mM dithiothreitol, 0.1 mM PMSF). Membranes (30,000×g pellet) were incubated for 15 min at 37 °C in 50 mM Tris‑HCl buffer (pH 7.5) containing 1 mM EDTA, 10 mM MgCl₂, 1 mM dithiothreitol, 1 mM IBMX, 1 mM ATP, 20 mM creatine phosphate, and 10 U creatine phosphokinase, with various concentrations of Flavoxate. Reaction stopped with 15% TCA, cAMP quantified by enzyme immunoassay. [1]
PTX pretreatment of membranes: PTX preactivated at 30 °C for 10 min in 50 mM Tris‑HCl pH 7.5 with 50 mM dithiothreitol and 1 mM ATP. Membranes incubated with preactivated PTX (10 μg/ml) for 1 h at 30 °C in TED buffer containing 1 mM ATP, 2 μM NAD, 10 mM thymidine. After washing, cAMP assay performed as above. [1]
Receptor binding assays: Various rat tissues homogenized, membranes incubated with tritiated ligands and Flavoxate (10⁻⁸ ‑ 10⁻⁴ M) for specific times and temperatures as detailed. Nonspecific binding determined with excess unlabeled ligands. Kᵢ values calculated. [1]

Rats; 10mg/kg

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Intracerebroventricular injection of PTX: Female Sprague‑Dawley rats (170‑250 g) anesthetized with pentobarbital (50 mg/kg i.p.). A stainless steel cannula inserted into lateral ventricle (coordinates: 1.5 mm lateral, 0.8 mm rostral to bregma, 3.5 mm below dura). PTX (1 μg in 5 μl of vehicle: 25 mM Tris buffer pH 8.0 containing 50% glycerol and 0.5 M NaCl) injected at 2.5 μl/min. Sham‑injected rats received vehicle only. Experiments performed 4 days later. [1]
Isovolumetric rhythmic bladder contraction: Rats anesthetized with urethane (900 mg/kg s.c.). Bladder cannulated via urethra with PE‑50 tubing, connected to pressure transducer and infusion pump. Bladder filled with warm saline (0.1 ml increments) until rhythmic contractions occurred (total volume 0.5‑0.8 ml). After stable contractions for 15 min, Flavoxate (3 mg/kg) injected intravenously. Inter‑contraction intervals measured for 15 min before and after drug. After experiments, striatum dissected for cAMP assay. [1]

Absorption, Distribution and Excretion
It is well absorbed in the gastrointestinal tract. 57% of flavonoid hydrochloride is excreted in the urine within 24 hours.

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Hepatotoxicity
As with other anticholinergic drugs, flavonoids have not been found to be associated with elevated liver enzymes or clinically significant liver injury. Its high safety profile is likely primarily due to its low daily dose. References regarding the safety and potential hepatotoxicity of anticholinergic drugs are listed after the "Overview of Anticholinergic Drugs" section. Drug Category: Anticholinergic Drugs

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Effects During Pregnancy and Lactation
◉ Overview of Use During Lactation There is currently no information regarding the use of flavonoids during lactation. Long-term use of trihexyphenidyl may reduce milk production or the milk ejection reflex, but a single dose is unlikely to affect breastfeeding. With long-term use, signs of reduced milk production (e.g., infant dissatisfaction, poor weight gain) should be observed. ◉ Effects on Breastfed Infants As of the revision date, no relevant published information was found.
◉ Effects on Lactation and Breast Milk
Anticholinergic drugs can inhibit lactation in animals, possibly by suppressing the secretion of growth hormone and oxytocin. Anticholinergic drugs can also lower serum prolactin levels in non-lactating women. Prolactin levels in established lactating mothers may not affect their ability to breastfeed.

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No toxicity data reported. [1]

Brain Res.1996 Jul 15;727(1-2):91-8.

Flavonoid ester is a carboxylic acid ester formed by the condensation of 3-methylflavonoid-8-carboxylic acid and 2-(1-piperidinyl)ethanol. It possesses parasympathetic blocking, muscarinic receptor antagonistic, and antispasmodic effects. It belongs to the piperidine, flavonoid, carboxylic acid ester, and tertiary amine classes. Its function is related to 3-methylflavonoid-8-carboxylic acid and 2-(piperidin-1-yl)ethanol. It is the conjugate base of flavonoid ester (1+). Flavonoid ester is a cholinergic muscarinic receptor antagonist. Its mechanism of action is as a cholinergic muscarinic receptor antagonist. Flavonoid ester is a synthetic anticholinergic drug used to treat urinary incontinence and overactive bladder. Flavonoid ester has not been shown to cause elevated liver enzymes or clinically significant acute liver injury. Flavonoid ester is a synthetic parasympathetic blocking agent with antimuscarinic, muscle relaxant, and urinary tract antispasmodic effects. Flavoxel can bind to and inhibit muscarinic receptors, thereby inhibiting the micturition reflex and increasing bladder capacity by modulating the brainstem micturition center. Furthermore, this drug has been found to inhibit the production of cyclic adenosine monophosphate (cAMP) in the striatum membrane of the brain by stimulating pertussis toxin-sensitive G protein-coupled receptors, thereby inhibiting isovolumetric bladder contraction. This drug has been used to treat various urinary system diseases and as an antispasmodic. Its therapeutic value and mechanism of action are not yet clear. It may have local anesthetic effects, a direct relaxant effect on smooth muscle, and some muscarinic receptor antagonistic effect. See also: Flavoxel hydrochloride (salt form). Indications: Used to relieve symptoms such as dysuria, urgency, nocturia, suprapubic pain, urinary frequency, and urinary incontinence caused by cystitis, prostatitis, urethritis, urethrocystitis/urethral triangle inflammation.

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Mechanism of Action
Flavorone acts as a direct antagonist of muscarinic acetylcholine receptors in cholinergic organs. Its anticholinergic-parasympathetic blocking effect reduces bladder smooth muscle tone, effectively reducing the frequency of urination, the frequency of urge incontinence, and the severity of urinary urgency, improving urinary retention, and increasing the volume of each urination.

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Flavoxate is clinically used for urinary frequency disorders. This study demonstrates that it inhibits cAMP formation in rat brain via activation of multiple Gi‑coupled receptors (A₁, D₂, α₂) in a cooperative manner, as antagonists only block when combined. The suppression of micturition reflex by Flavoxate in rats is mediated by brain pertussis toxin‑sensitive G proteins, likely in the nucleus reticularis pontis oralis or striatum. [1]

C24H25NO4

391.18

391.178

15301-69-6

Flavoxate hydrochloride;3717-88-2;Flavoxate-d5;2748541-85-5

3354

Typically exists as solid at room temperature

1.2±0.1 g/cm3

564.1±50.0 °C at 760 mmHg

232-234

294.9±30.1 °C

0.0±1.5 mmHg at 25°C

1.591

5.18

0

5

6

29

631

0

CC1=C(C2=CC=CC=C2)OC3=C(C=CC=C3C(=O)OCCN4CCCCC4)C1=O

Flavoxate, Spasuret, Uronid, Urispas, Bladuril;Rec-7-0040; DW-61; NSC-114649;Rec 7-0040; DW 61; NSC 114649;Rec7-0040; DW61; NSC114649

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO: >10 mM Water:<1 mg/mL Ethanol:

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)