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Details

Stereochemistry ABSOLUTE
Molecular Formula C22H19N3O4
Molecular Weight 389.404
Optical Activity UNSPECIFIED
Defined Stereocenters 2 / 2
E/Z Centers 0
Charge 0

SHOW SMILES / InChI
Structure of TADALAFIL

SMILES

[H][C@]12CC3=C(NC4=C3C=CC=C4)[C@H](N1C(=O)CN(C)C2=O)C5=CC6=C(OCO6)C=C5

InChI

InChIKey=WOXKDUGGOYFFRN-IIBYNOLFSA-N
InChI=1S/C22H19N3O4/c1-24-10-19(26)25-16(22(24)27)9-14-13-4-2-3-5-15(13)23-20(14)21(25)12-6-7-17-18(8-12)29-11-28-17/h2-8,16,21,23H,9-11H2,1H3/t16-,21-/m1/s1

HIDE SMILES / InChI

Molecular Formula C22H19N3O4
Molecular Weight 389.404
Charge 0
Count
MOL RATIO 1 MOL RATIO (average)
Stereochemistry ABSOLUTE
Additional Stereochemistry No
Defined Stereocenters 2 / 2
E/Z Centers 0
Optical Activity UNSPECIFIED

Description

Tadalafil is used to treat male erectile dysfunction (impotence) and pulmonary arterial hypertension (PAH). Part of the physiological process of erection involves the release of nitric oxide (NO) in the corpus cavernosum. This then activates the enzyme guanylate cyclase which results in increased levels of cyclic guanosine monophosphate (cGMP), leading to smooth muscle relaxation in the corpus cavernosum, resulting in increased inflow of blood and an erection. Tadalafil is a potent and selective inhibitor of cGMP specific phosphodiesterase type 5 (PDE5) which is responsible for degradation of cGMP in the corpus cavernosum. This means that, with tadalafil on board, normal sexual stimulation leads to increased levels of cGMP in the corpus cavernosum which leads to better erections. Without sexual stimulation and no activation of the NO/cGMP system, tadalafil should not cause an erection.Tadalafil inhibits the cGMP specific phosphodiesterase type 5 (PDE5) which is responsible for degradation of cGMP in the corpus cavernosum located around the penis. Penile erection during sexual stimulation is caused by increased penile blood flow resulting from the relaxation of penile arteries and corpus cavernosal smooth muscle. This response is mediated by the release of nitric oxide (NO) from nerve terminals and endothelial cells, which stimulates the synthesis of cGMP in smooth muscle cells. Cyclic GMP causes smooth muscle relaxation and increased blood flow into the corpus cavernosum. The inhibition of phosphodiesterase type 5 (PDE5) by tadalafil enhances erectile function by increasing the amount of cGMP. Tadalafil is used for the treatment of erectile dysfunction.

CNS Activity

Originator

Approval Year

Targets

Primary TargetPharmacologyConditionPotency
100.0 µM [IC50]
5.1 µM [IC50]
0.05 µM [IC50]
5.0 nM [IC50]

Conditions

ConditionModalityTargetsHighest PhaseProduct
Primary
CIALIS
Primary
CIALIS

Cmax

ValueDoseCo-administeredAnalytePopulation
308.1 μg/L
20 mg single, oral
TADALAFIL blood
Homo sapiens

AUC

ValueDoseCo-administeredAnalytePopulation
7225 μg × h/L
20 mg single, oral
TADALAFIL blood
Homo sapiens

T1/2

ValueDoseCo-administeredAnalytePopulation
17.4 h
20 mg single, oral
TADALAFIL blood
Homo sapiens

Funbound

ValueDoseCo-administeredAnalytePopulation
6%
40 mg single, oral
TADALAFIL unknown
Homo sapiens

Doses

AEs

Drug as perpetrator​

Drug as victim

Tox targets

PubMed

Sample Use Guides

In Vivo Use Guide
ED: Starting dose: 10 mg as needed prior to sexual activity. Increase to 20 mg or decrease to 5 mg based upon efficacy/tolerability. Improves erectile function compared to placebo up to 36 hours post dose. Not to be taken more than once per day
Route of Administration: Oral
In Vitro Use Guide
Increasing levels of tadalafil (1–25 uM) attenuated proliferation of human primary prostatic stromal cells (PrSCs) in a dose-dependent manner with concentrations above 5 uM showing highly significant effects
Substance Class Chemical
Record UNII
742SXX0ICT
Record Status Validated (UNII)
Record Version