Silodosin

Identification

Summary

Silodosin is an alpha-1 adrenergic receptor antagonist used to treat symptoms associated with benign prostatic hyperplasia (BPH).

Brand Names
Rapaflo, Silodyx, Urorec
Generic Name
Silodosin
DrugBank Accession Number
DB06207
Background

Silodosin is a selective antagonist of alpha(α)-1 adrenergic receptors that binds to the α1A subtype with the highest affinity. α1-adrenergic receptors regulate smooth muscle tone in the bladder neck, prostate, and prostatic urethra: the α1A subtype accounts for approximately 75% of α1-adrenoceptors in the prostate.2

Silodosin was first approved by the FDA in October 2008 2 and it is also approved in Europe and Canada. Silodosin is available as oral capsules with common trade names Rapaflo and Urorec. It is indicated for the symptomatic treatment of benign prostatic hyperplasia in adults.7 Most commonly affecting males over the age of 40 years, benign prostatic hyperplasia is the non-malignant enlargement of the prostate gland, associated with lower urinary tract symptoms that have a negative impact on the quality of life of patients.2 Silodosin works by binding to α1A-adrenoceptors with high affinity and relaxing the lower urinary tract, thereby improving urinary symptoms and alleviating bladder outlet obstruction.6

Type
Small Molecule
Groups
Approved
Structure
Weight
Average: 495.5345
Monoisotopic: 495.234491142
Chemical Formula
C25H32F3N3O4
Synonyms
  • Silodosin
  • Silodosina
External IDs
  • KAD 3213
  • KAD-3213
  • KMD 3213
  • KMD-3213

Pharmacology

Indication

Silodosin is indicated for the treatment of the signs and symptoms of benign prostatic hyperplasia (BPH). It is not indicated for the treatment of hypertension.7

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Associated Conditions
Indication TypeIndicationCombined Product DetailsApproval LevelAge GroupPatient CharacteristicsDose Form
Symptomatic treatment ofBenign prostatic hyperplasia•••••••••••••••••••
Contraindications & Blackbox Warnings
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Pharmacodynamics

Silodosin is an antagonist of α1-adrenoceptors. It has the highest selectivity for the α1A-adrenoceptor subtype, with a 162-fold greater affinity than α1B-adrenoceptor and about a 50-fold greater affinity than for α1D-adrenoceptor. In clinical trials, silodosin improved maximum urinary flow rate, voiding symptoms, and storage symptoms of benign prostatic hyperplasia.2,3 Following oral administration, silodosin had a rapid onset of effect in men,3 with early effects of relieving lower urinary tract symptoms occurring within two to six hours post-dose.6

Silodosin inhibited the human ether-a-go-go-related gene (HERG) tail current; however, it has weak cardiovascular effects.5 As with all α1-adrenoceptor antagonists blocking α1-adrenoceptors in the iris dilator muscle, silodosin may cause intraoperative floppy iris syndrome (IFIS), which is characterized by small pupils and iris billowing during cataract surgery in patients taking α1-AR antagonists.6

Mechanism of action

The pathogenesis of benign prostatic hyperplasia is not fully understood: it is believed to involve several pathways, including inflammation, apoptosis, and cellular proliferation. Most drug therapies aim to alleviate symptoms of benign prostatic hyperplasia, silodosin included. Lower urinary tract symptoms of benign prostatic hyperplasia are categorized into three main groups: voiding or obstructive (hesitancy, slow stream, intermittency, incomplete emptying), storage or irritative (frequency, urgency, nocturia, urge urinary incontinence), and postmicturition (postvoid dribbling). Prostate contraction is the main contributor to lower urinary tract symptoms of benign prostatic hyperplasia. The smooth muscle tone of the prostate is regulated by α1A-adrenoceptors, which are the most highly expressed subtype of α1adrenoceptors in the human prostate tissue.2 It has been reported that blockade of α1A-adrenoceptors relieves bladder outlet obstruction. Blockade of α1D-adrenoceptors, another subtype found in prostate tissue, is believed to alleviate storage symptoms due to detrusor overactivity.6

α1-adrenoceptors are G protein-coupled receptors: upon binding of its natural ligand, norepinephrine and epinephrine, leads to the activation of phospholipase C and downstream signalling molecules, including inositol triphosphate and diacylglycerol. Ultimately, there is an increase in intracellular calcium levels and, consequently, smooth muscle contraction. Silodosin is an antagonist of α1-adrenoceptors, with the highest selectivity for the α1A-adrenoceptor subtype. By blocking the α1A-adrenoceptor signalling pathway, silodosin promotes prostatic and urethral smooth muscle relaxation, thereby improving lower urinary tract symptoms such as voiding. Silodosin also targets afferent nerves in the bladder, relieving bladder overactivity and storage symptoms.2

TargetActionsOrganism
AAlpha-1A adrenergic receptor
antagonist
Humans
AAlpha-1D adrenergic receptor
antagonist
Humans
AAlpha-1B adrenergic receptor
antagonist
Humans
UHERG human cardiac K+ channel
blocker
Humans
Absorption

The absolute bioavailability is approximately 32%. Following oral administration of silodosin 8 mg once daily in healthy male subjects, Cmax was 61.6 ± 27.54 ng/mL and AUC was 373.4 ± 164.94 ng x hr/mL. The Tmax was 2.6 ± 0.90 hours.7 Silodosin glucuronide or KMD-3213G, the main metabolite of silodosin, has an AUC three- or four fold higher than for the parent compound.2

A moderate fat or calorie meal reduces Cmax by 18% to 43% and AUC by 4% to 49%, as well as Tmax by about one hour. However, the US prescribing information recommends drug intake with meals to avoid the potential adverse effects associated with high plasma drug concentrations.7

Volume of distribution

Silodosin has an apparent volume of distribution of 49.5 L.7

Protein binding

Silodosin is approximately 97% protein bound.7

Metabolism

The main metabolite of silodosin is silodosin glucuronide (KMD-3213G), which is a pharmacologically active metabolite formed by direct glucuronide conjugation mediated by UDP-glucuronosyltransferase 2B7 (UGT2B7). Silodosin glucuronide reaches plasma exposure (AUC) approximately four times greater than that of silodosin. The second major metabolite, KMD-3293, is formed from dehydrogenation catalyzed by alcohol and aldehyde dehydrogenases. KMD-3293 has negligible pharmacological activity and reaches plasma exposures similar to that of silodosin. Silodosin is also metabolized by CYP3A4, which catalyzes the oxidation reaction.7

Other than glucuronidation, dehydrogenation, and oxidation as its main metabolic pathways, silodosin can also undergo dealkylation (KMD-3289), N-dealkylation, hydroxylation, glucosylation, and sulfate conjugation. Metabolites of silodosin can undergo a series of further metabolic pathways.4

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Route of elimination

At 10 days following oral administration of radiolabelled silodosin, about 33.5% of the dose was recovered in urine and 54.9% was recovered in feces.7

Half-life

The elimination half-life of silodosin is 13.3 ± 8.07 hours. KMD-3213G, the main metabolite of silodosin, has an extended half-life of approximately 24 hours.7

Clearance

After intravenous administration, the plasma clearance of silodosin was approximately 10 L/hour. 7

Adverse Effects
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Toxicity

Oral LD50 is 800 mg/kg in rats.8

In clinical trials, postural hypotension was the most common dose-limiting adverse event. In case of drug overdose leading to hypotension, the patient should be placed in a supine position to restore blood pressure and normalize heart rate. Further measures, such as administration of intravenous fluids, may be initiated. In case of the use of vasopressors, renal function should be monitored and supported as needed. Since silodosin is highly bound to plasma proteins, dialysis is unlikely to be beneficial.7

Pathways
Not Available
Pharmacogenomic Effects/ADRs Browse all" title="About SNP Mediated Effects/ADRs" id="snp-actions-info" class="drug-info-popup" href="javascript:void(0);">
Not Available

Interactions

Drug Interactions Learn More" title="About Drug Interactions" id="structured-interactions-info" class="drug-info-popup" href="javascript:void(0);">
This information should not be interpreted without the help of a healthcare provider. If you believe you are experiencing an interaction, contact a healthcare provider immediately. The absence of an interaction does not necessarily mean no interactions exist.
DrugInteraction
AbametapirThe serum concentration of Silodosin can be increased when it is combined with Abametapir.
AbemaciclibThe serum concentration of Abemaciclib can be increased when it is combined with Silodosin.
AbrocitinibThe excretion of Silodosin can be decreased when combined with Abrocitinib.
AcebutololThe risk or severity of orthostatic hypotension and dizziness can be increased when Acebutolol is combined with Silodosin.
AdagrasibThe excretion of Silodosin can be decreased when combined with Adagrasib.
Food Interactions
  • Take with food. A moderate fat or calorie meal decreases drug exposure as well as the risk of adverse effects.

Products

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Product Images
International/Other Brands
Rapilif (Ipca Urosciences ) / Urief (Watson Pharmaceuticals Inc.)
Brand Name Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing EndRegionImage
RapafloCapsule4 mg/1OralAllergan, Inc.2009-03-23Not applicableUS flag
RapafloCapsule4 mgOralAllergan2011-10-262021-12-06Canada flag
RapafloCapsule4 mg/1OralActavis Pharma, Inc.2009-03-232020-10-31US flag
RapafloCapsule8 mg/1OralAllergan, Inc.2009-03-23Not applicableUS flag
RapafloCapsule8 mg/1OralAvera McKennan Hospital2015-03-232017-05-24US flag
Generic Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing EndRegionImage
Ag-silodosinCapsule8 mgOralAngita Pharma Inc.Not applicableNot applicableCanada flag
Ag-silodosinCapsule4 mgOralAngita Pharma Inc.Not applicableNot applicableCanada flag
Apo-silodosinCapsule4 mgOralApotex CorporationNot applicableNot applicableCanada flag
Auro-silodosinCapsule4 mgOralAuro Pharma Inc2022-02-16Not applicableCanada flag
Auro-silodosinCapsule8 mgOralAuro Pharma Inc2022-02-16Not applicableCanada flag

Categories

ATC Codes
G04CA04 — Silodosin
Drug Categories
Chemical TaxonomyProvided by Classyfire
Description
This compound belongs to the class of organic compounds known as indolecarboxamides and derivatives. These are compounds containing a carboxamide group attached to an indole.
Kingdom
Organic compounds
Super Class
Organoheterocyclic compounds
Class
Indoles and derivatives
Sub Class
Indolecarboxylic acids and derivatives
Direct Parent
Indolecarboxamides and derivatives
Alternative Parents
Dialkylarylamines / Phenol ethers / Phenoxy compounds / Alkyl aryl ethers / Aralkylamines / Vinylogous amides / 1,3-aminoalcohols / Amino acids and derivatives / Primary carboxylic acid amides / Dialkylamines
show 7 more
Substituents
1,3-aminoalcohol / Alcohol / Alkanolamine / Alkyl aryl ether / Alkyl fluoride / Alkyl halide / Amine / Amino acid or derivatives / Aralkylamine / Aromatic heteropolycyclic compound
show 26 more
Molecular Framework
Aromatic heteropolycyclic compounds
External Descriptors
Not Available
Affected organisms
  • Humans and other mammals

Chemical Identifiers

UNII
CUZ39LUY82
CAS number
160970-54-7
InChI Key
PNCPYILNMDWPEY-QGZVFWFLSA-N
InChI
InChI=1S/C25H32F3N3O4/c1-17(30-8-12-34-21-5-2-3-6-22(21)35-16-25(26,27)28)13-18-14-19-7-10-31(9-4-11-32)23(19)20(15-18)24(29)33/h2-3,5-6,14-15,17,30,32H,4,7-13,16H2,1H3,(H2,29,33)/t17-/m1/s1
IUPAC Name
1-(3-hydroxypropyl)-5-[(2R)-2-({2-[2-(2,2,2-trifluoroethoxy)phenoxy]ethyl}amino)propyl]-2,3-dihydro-1H-indole-7-carboxamide
SMILES
C[C@H](CC1=CC2=C(N(CCCO)CC2)C(=C1)C(N)=O)NCCOC1=CC=CC=C1OCC(F)(F)F

References

General References
  1. Yoshida M, Homma Y, Kawabe K: Silodosin, a novel selective alpha 1A-adrenoceptor selective antagonist for the treatment of benign prostatic hyperplasia. Expert Opin Investig Drugs. 2007 Dec;16(12):1955-65. [Article]
  2. Rossi M, Roumeguere T: Silodosin in the treatment of benign prostatic hyperplasia. Drug Des Devel Ther. 2010 Oct 27;4:291-7. doi: 10.2147/DDDT.S10428. [Article]
  3. Keating GM: Silodosin: a review of its use in the treatment of the signs and symptoms of benign prostatic hyperplasia. Drugs. 2015 Feb;75(2):207-17. doi: 10.1007/s40265-014-0344-z. [Article]
  4. Vishnuvardhan C, Baikadi S, Borkar RM, Srinivas R, Satheeshkumar N: In vivo metabolic investigation of silodosin using UHPLC-QTOF-MS/MS and in silico toxicological screening of its metabolites. J Mass Spectrom. 2016 Oct;51(10):867-882. doi: 10.1002/jms.3795. [Article]
  5. Tatemichi S, Kiguchi S, Kobayashi M, Yamazaki Y, Shibata N, Uruno T: Cardiovascular effects of the selective alphalA-adrenoceptor antagonist silodosin (KMD-3213), a drug for the treatment of voiding dysfunction. Arzneimittelforschung. 2006;56(10):682-7. doi: 10.1055/s-0031-1296773. [Article]
  6. Yamanishi T, Mizuno T, Kamai T, Yoshida K, Sakakibara R, Uchiyama T: Management of benign prostatic hyperplasia with silodosin. Open Access J Urol. 2009 Aug 20;1:1-7. doi: 10.2147/rru.s5004. [Article]
  7. FDA Approved Drug Products: RAPAFLO (silodosin) Capsule for oral use [Link]
  8. Biosynth Carbosynth: Silodosin Safety Data Sheet [Link]
  9. Selleck Chemicals: Silodosin Safety Data Sheet [Link]
KEGG Drug
D01965
PubChem Compound
5312125
PubChem Substance
175427058
ChemSpider
4471557
BindingDB
50160154
RxNav
720825
ChEBI
135929
ChEMBL
CHEMBL24778
ZINC
ZINC000003806063
PharmGKB
PA165291889
RxList
RxList Drug Page
Drugs.com
Drugs.com Drug Page
Wikipedia
Silodosin
FDA label
Download (846 KB)
MSDS
Download (479 KB)

Clinical Trials

Clinical Trials Learn More" title="About Clinical Trials" id="clinical-trials-info" class="drug-info-popup" href="javascript:void(0);">
PhaseStatusPurposeConditionsCount
4CompletedTreatmentBenign Prostatic Hyperplasia (BPH)3
4CompletedTreatmentBenign Prostatic Hyperplasia (BPH) / Nocturia1
4CompletedTreatmentBenign Prostatic Hypertrophy1
4CompletedTreatmentNeurogenic Bladder / Voiding Dysfunction1
4CompletedTreatmentUreteral Stones1

Pharmacoeconomics

Manufacturers
Not Available
Packagers
Not Available
Dosage Forms
FormRouteStrength
CapsuleOral8 mg/1
CapsuleOral
CapsuleOral4 mg/1
Capsule, gelatin coatedOral4 mg/1
Capsule, gelatin coatedOral8 mg/1
CapsuleOral4 MG
CapsuleOral8 MG
Capsule, coatedOral8 mg
Capsule, coatedOral4 mg
Tablet; tablet, film coatedOral
Tablet, film coatedOral
Tablet, film coatedOral4 mg
Tablet, coatedOral4 mg
Prices
Not Available
Patents
Patent NumberPediatric ExtensionApprovedExpires (estimated)Region
US5403847No1995-04-042012-11-13US flag
US5387603No1995-02-072018-12-01US flag

Properties

State
Solid
Experimental Properties
PropertyValueSource
melting point (°C)105 - 109°CFDA label
water solubility<1 mg/mLSelleck Chemicals MSDS
Predicted Properties
PropertyValueSource
Water Solubility0.0111 mg/mLALOGPS
logP2.96ALOGPS
logP3.05Chemaxon
logS-4.6ALOGPS
pKa (Strongest Acidic)14.87Chemaxon
pKa (Strongest Basic)9.66Chemaxon
Physiological Charge1Chemaxon
Hydrogen Acceptor Count6Chemaxon
Hydrogen Donor Count3Chemaxon
Polar Surface Area97.05 Å2Chemaxon
Rotatable Bond Count14Chemaxon
Refractivity128.92 m3·mol-1Chemaxon
Polarizability49.89 Å3Chemaxon
Number of Rings3Chemaxon
Bioavailability1Chemaxon
Rule of FiveYesChemaxon
Ghose FilterNoChemaxon
Veber's RuleNoChemaxon
MDDR-like RuleYesChemaxon
Predicted ADMET Features
PropertyValueProbability
Human Intestinal Absorption+1.0
Blood Brain Barrier+0.7383
Caco-2 permeable-0.5847
P-glycoprotein substrateSubstrate0.8467
P-glycoprotein inhibitor INon-inhibitor0.5833
P-glycoprotein inhibitor IIInhibitor0.7864
Renal organic cation transporterNon-inhibitor0.7288
CYP450 2C9 substrateNon-substrate0.8226
CYP450 2D6 substrateNon-substrate0.6362
CYP450 3A4 substrateSubstrate0.6585
CYP450 1A2 substrateNon-inhibitor0.7439
CYP450 2C9 inhibitorNon-inhibitor0.7569
CYP450 2D6 inhibitorNon-inhibitor0.5958
CYP450 2C19 inhibitorNon-inhibitor0.5562
CYP450 3A4 inhibitorInhibitor0.7424
CYP450 inhibitory promiscuityHigh CYP Inhibitory Promiscuity0.5723
Ames testNon AMES toxic0.6667
CarcinogenicityNon-carcinogens0.8529
BiodegradationNot ready biodegradable1.0
Rat acute toxicity2.4845 LD50, mol/kg Not applicable
hERG inhibition (predictor I)Weak inhibitor0.98
hERG inhibition (predictor II)Inhibitor0.8366
ADMET data is predicted using admetSAR, a free tool for evaluating chemical ADMET properties. (23092397)

Spectra

Mass Spec (NIST)
Not Available
Spectra
SpectrumSpectrum TypeSplash Key
LC-MS/MS Spectrum - LC-ESI-qTof , PositiveLC-MS/MSsplash10-014i-0121090000-11833eeb1f3c76d92dda
LC-MS/MS Spectrum - LC-ESI-qTof , PositiveLC-MS/MSsplash10-01ot-1490800000-2175bd3c7bc607b74fee
LC-MS/MS Spectrum - LC-ESI-qTof , PositiveLC-MS/MSsplash10-000x-1980000000-5d01eb798b6009518223
MS/MS Spectrum - , positiveLC-MS/MSsplash10-014i-0121090000-11833eeb1f3c76d92dda
MS/MS Spectrum - , positiveLC-MS/MSsplash10-01ot-1490800000-2175bd3c7bc607b74fee
MS/MS Spectrum - , positiveLC-MS/MSsplash10-000x-1980000000-5d01eb798b6009518223
Predicted MS/MS Spectrum - 10V, Positive (Annotated)Predicted LC-MS/MSsplash10-0uka-0029400000-4c49da9310a276b39c94
Predicted MS/MS Spectrum - 10V, Negative (Annotated)Predicted LC-MS/MSsplash10-00ko-0041900000-9bf3838899ac291685b2
Predicted MS/MS Spectrum - 20V, Positive (Annotated)Predicted LC-MS/MSsplash10-0h01-0042900000-7e94f644f809ba3f1b00
Predicted MS/MS Spectrum - 20V, Negative (Annotated)Predicted LC-MS/MSsplash10-0fsl-1336900000-b5f8cf51c7c40abd83b5
Predicted MS/MS Spectrum - 40V, Positive (Annotated)Predicted LC-MS/MSsplash10-03di-1194300000-dc43297567e08f12c294
Predicted MS/MS Spectrum - 40V, Negative (Annotated)Predicted LC-MS/MSsplash10-006x-0553900000-c4e23b7579e8f01ec125
Predicted 1H NMR Spectrum1D NMRNot Applicable
Predicted 13C NMR Spectrum1D NMRNot Applicable
Chromatographic Properties
Collision Cross Sections (CCS)
AdductCCS Value (Å2)Source typeSource
[M-H]-202.44289
predicted
DeepCCS 1.0 (2019)
[M+H]+204.80089
predicted
DeepCCS 1.0 (2019)
[M+Na]+210.89406
predicted
DeepCCS 1.0 (2019)

Targets

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Kind
Protein
Organism
Humans
Pharmacological action
Yes
Actions
Antagonist
General Function
Protein heterodimerization activity
Specific Function
This alpha-adrenergic receptor mediates its action by association with G proteins that activate a phosphatidylinositol-calcium second messenger system. Its effect is mediated by G(q) and G(11) prot...
Gene Name
ADRA1A
Uniprot ID
P35348
Uniprot Name
Alpha-1A adrenergic receptor
Molecular Weight
51486.005 Da
References
  1. Lepor H, Hill LA: Silodosin for the treatment of benign prostatic hyperplasia: pharmacology and cardiovascular tolerability. Pharmacotherapy. 2010 Dec;30(12):1303-12. doi: 10.1592/phco.30.12.1303. [Article]
  2. Yamada S, Kato Y, Okura T, Kagawa Y, Kawabe K: Prediction of alpha1-adrenoceptor occupancy in the human prostate from plasma concentrations of silodosin, tamsulosin and terazosin to treat urinary obstruction in benign prostatic hyperplasia. Biol Pharm Bull. 2007 Jul;30(7):1237-41. [Article]
  3. Yamanishi T, Mizuno T, Kamai T, Yoshida K, Sakakibara R, Uchiyama T: Management of benign prostatic hyperplasia with silodosin. Open Access J Urol. 2009 Aug 20;1:1-7. doi: 10.2147/rru.s5004. [Article]
Kind
Protein
Organism
Humans
Pharmacological action
Yes
Actions
Antagonist
General Function
Alpha1-adrenergic receptor activity
Specific Function
This alpha-adrenergic receptor mediates its effect through the influx of extracellular calcium.
Gene Name
ADRA1D
Uniprot ID
P25100
Uniprot Name
Alpha-1D adrenergic receptor
Molecular Weight
60462.205 Da
References
  1. Berman HM, Westbrook J, Feng Z, Gilliland G, Bhat TN, Weissig H, Shindyalov IN, Bourne PE: The Protein Data Bank. Nucleic Acids Res. 2000 Jan 1;28(1):235-42. [Article]
  2. Yamanishi T, Mizuno T, Kamai T, Yoshida K, Sakakibara R, Uchiyama T: Management of benign prostatic hyperplasia with silodosin. Open Access J Urol. 2009 Aug 20;1:1-7. doi: 10.2147/rru.s5004. [Article]
Kind
Protein
Organism
Humans
Pharmacological action
Yes
Actions
Antagonist
General Function
Protein heterodimerization activity
Specific Function
This alpha-adrenergic receptor mediates its action by association with G proteins that activate a phosphatidylinositol-calcium second messenger system. Its effect is mediated by G(q) and G(11) prot...
Gene Name
ADRA1B
Uniprot ID
P35368
Uniprot Name
Alpha-1B adrenergic receptor
Molecular Weight
56835.375 Da
References
  1. Lepor H, Hill LA: Silodosin for the treatment of benign prostatic hyperplasia: pharmacology and cardiovascular tolerability. Pharmacotherapy. 2010 Dec;30(12):1303-12. doi: 10.1592/phco.30.12.1303. [Article]
  2. Sugawara T, Hirasawa A, Hashimoto K, Tsujimoto G: Differences in the subcellular localization of alpha1-adrenoceptor subtypes can affect the subtype selectivity of drugs in a study with the fluorescent ligand BODIPY FL-prazosin. Life Sci. 2002 Mar 22;70(18):2113-24. doi: 10.1016/s0024-3205(01)01533-8. [Article]
  3. Yamanishi T, Mizuno T, Kamai T, Yoshida K, Sakakibara R, Uchiyama T: Management of benign prostatic hyperplasia with silodosin. Open Access J Urol. 2009 Aug 20;1:1-7. doi: 10.2147/rru.s5004. [Article]
Kind
Protein group
Organism
Humans
Pharmacological action
Unknown
Actions
Blocker
General Function
Voltage-gated potassium channel activity involved in ventricular cardiac muscle cell action potential repolarization
Specific Function
Pore-forming (alpha) subunit of voltage-gated inwardly rectifying potassium channel. Channel properties are modulated by cAMP and subunit assembly. Mediates the rapidly activating component of the ...

Components:
References
  1. Tatemichi S, Kiguchi S, Kobayashi M, Yamazaki Y, Shibata N, Uruno T: Cardiovascular effects of the selective alphalA-adrenoceptor antagonist silodosin (KMD-3213), a drug for the treatment of voiding dysfunction. Arzneimittelforschung. 2006;56(10):682-7. doi: 10.1055/s-0031-1296773. [Article]

Enzymes

Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
General Function
Glucuronosyltransferase activity
Specific Function
UDPGT is of major importance in the conjugation and subsequent elimination of potentially toxic xenobiotics and endogenous compounds.Its unique specificity for 3,4-catechol estrogens and estriol su...
Gene Name
UGT2B7
Uniprot ID
P16662
Uniprot Name
UDP-glucuronosyltransferase 2B7
Molecular Weight
60694.12 Da
References
  1. FDA Approved Drug Products: RAPAFLO (silodosin) Capsule for oral use [Link]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
General Function
Electron carrier activity
Specific Function
Not Available
Gene Name
ALDH2
Uniprot ID
P05091
Uniprot Name
Aldehyde dehydrogenase, mitochondrial
Molecular Weight
56380.93 Da
References
  1. FDA Approved Drug Products: RAPAFLO (silodosin) Capsule for oral use [Link]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
General Function
L-glucuronate reductase activity
Specific Function
Catalyzes the NADPH-dependent reduction of a variety of aromatic and aliphatic aldehydes to their corresponding alcohols. Catalyzes the reduction of mevaldate to mevalonic acid and of glyceraldehyd...
Gene Name
AKR1A1
Uniprot ID
P14550
Uniprot Name
Alcohol dehydrogenase [NADP(+)]
Molecular Weight
36572.71 Da
References
  1. FDA Approved Drug Products: RAPAFLO (silodosin) Capsule for oral use [Link]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
General Function
Vitamin d3 25-hydroxylase activity
Specific Function
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It performs a variety of oxidation react...
Gene Name
CYP3A4
Uniprot ID
P08684
Uniprot Name
Cytochrome P450 3A4
Molecular Weight
57342.67 Da
References
  1. Matsubara Y, Kanazawa T, Kojima Y, Abe Y, Kobayashi K, Kanbe H, Harada H, Momose Y, Terakado S, Adachi Y, Midgley I: [Pharmacokinetics and disposition of silodosin (KMD-3213)]. Yakugaku Zasshi. 2006 Mar;126 Spec no.:237-45. [Article]
  2. Cantrell MA, Bream-Rouwenhorst HR, Hemerson P, Magera JS Jr: Silodosin for benign prostatic hyperplasia. Ann Pharmacother. 2010 Feb;44(2):302-10. doi: 10.1345/aph.1M320. Epub 2010 Jan 13. [Article]
  3. FDA Approved Drug Products: RAPAFLO (silodosin) Capsule for oral use [Link]

Transporters

Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
General Function
Xenobiotic-transporting atpase activity
Specific Function
Energy-dependent efflux pump responsible for decreased drug accumulation in multidrug-resistant cells.
Gene Name
ABCB1
Uniprot ID
P08183
Uniprot Name
Multidrug resistance protein 1
Molecular Weight
141477.255 Da
References
  1. Matsubara Y, Kanazawa T, Kojima Y, Abe Y, Kobayashi K, Kanbe H, Harada H, Momose Y, Terakado S, Adachi Y, Midgley I: [Pharmacokinetics and disposition of silodosin (KMD-3213)]. Yakugaku Zasshi. 2006 Mar;126 Spec no.:237-45. [Article]
  2. FDA Approved Drug Products: RAPAFLO (silodosin) Capsule for oral use [Link]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
General Function
Xenobiotic-transporting atpase activity
Specific Function
Energy-dependent phospholipid efflux translocator that acts as a positive regulator of biliary lipid secretion. Functions as a floppase that translocates specifically phosphatidylcholine (PC) from ...
Gene Name
ABCB4
Uniprot ID
P21439
Uniprot Name
Phosphatidylcholine translocator ABCB4
Molecular Weight
141521.845 Da
References
  1. Matsubara Y, Kanazawa T, Kojima Y, Abe Y, Kobayashi K, Kanbe H, Harada H, Momose Y, Terakado S, Adachi Y, Midgley I: [Pharmacokinetics and disposition of silodosin (KMD-3213)]. Yakugaku Zasshi. 2006 Mar;126 Spec no.:237-45. [Article]

Drug created at March 19, 2008 16:17 / Updated at February 20, 2024 23:54