KTX

Uses

KTX is used for the treatment of erectile dysfunction (ED).

KTX is used for the treatment of the signs and symptoms of benign prostatic hyperplasia (BPH).

KTX is used for the treatment of erectile dysfunction and the signs of benign prostatic hyperplasia (ED/BPH).

KTX is also used to associated treatment for these conditions: Benign Prostatic Hyperplasia (BPH), Erectile Dysfunction, Symptomatic pulmonary arterial hypertension (PAH)

How KTX works

Penile erection during sexual stimulation is achieved by the relaxation of penile arteries and corpus cavernosal smooth muscles, leading to increased blood flow to the organ. 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, and is degraded by the cGMP specific phosphodiesterase type 5 (PDE5) in the corpus cavernosum located around the penis. KTX inhibits PDE5 and thereby enhances erectile function by increasing the amount of cGMP available.

Dosage

KTX dosage

Erectile Dysfunction-

For Use as Needed:

• The recommended starting dose of KTX for use as needed in most patients is 10 mg, taken prior to anticipated sexual activity.
• The dose may be increased to 20 mg or decreased to 5 mg, based on individual efficacy and tolerability. The maximum recommended dosing frequency is once per day in most patients.

For Once Daily Use:

• The recommended starting dose of KTX for once daily use is 2.5 mg, taken at approximately the same time every day, without regard to timing of sexual activity.
• The KTX dose for once daily use may be increased to 5 mg, based on individual efficacy and tolerability.

Patients with BPH or with ED and BPH-

• Intimate for once daily use for BPH: The recommended dose of Intimate for once daily use is 5 mg, taken at approximately the same time every day.
• Intimate for once daily use for ED+BPH: The recommended dose of Intimate for once daily use is 5 mg, taken at approximately the same time every day, without regard to timing of sexual activity.

KTX may be taken without regard to food.

Side Effects

Body as a whole: hypersensitivity reactions including rash, urticaria, facial edema, Stevens-Johnson syndrome, and exfoliative dermatitis.

Cardiovascular and cerebrovascular: Serious cardiovascular events, including myocardial infarction, sudden cardiac death, unstable angina pectoris, ventricular arrhythmia, stroke, transient ischemic attacks, chest pain, palpitations, and tachycardia, may occur. Most of the patients in whom these events have been reported had pre-existing cardiovascular risk factors. Hypotension (more commonly reported when tadalafil is given to patients who are already taking antihypertensive agents), hypertension, and syncope.

Skin and subcutaneous tissues: hyperhidrosis (sweating).

Gastrointestinal: abdominal pain and gastroesophageal reflux.

Nervous system: migraine, transient global amnesia.Respiratory system: epistaxis (nose bleed).

Special senses: blurred vision, nonarteritic anterior ischemic optic neuropathy, retinal vein occlusion, visual field defect.

Otologic: cases of sudden decrease or loss of hearing have been reported.

Toxicity

Oral, Rat LD₅₀ = 2000 mg/kg, no deaths or toxicity.

Precaution

Cardiovascular: Physicians should consider the cardiovascular status of their patients, since there is a degree of cardiac risk associated with sexual activity. Potential for Drug Interactions When Taking KTX for Once Daily Use Physicians should be aware that KTX for once daily use provides continuous plasma KTX levels and should consider this when evaluating the potential for interactions with medications (e.g., nitrates, alpha-blockers, anti-hypertensives and potent inhibitors of CYP3A4).

Prolonged Erection: There have been rare reports of prolonged erections greater than 4 hours and priapism (painful erections greater than 6 hours in duration) for this class of compounds. Priapism, if not treated promptly, can result in irreversible damage to the erectile tissue. Patients who have an erection lasting greater than 4 hours, whether painful or not, should seek emergency medical attention. KTX should be used with caution in patients who have conditions that might predispose them to priapism (such as sickle cell anemia, multiple myeloma, or leukemia), or in patients with anatomical deformation of the penis (such as angulation, cavernosal fibrosis, or Peyronie’s disease).

Eye & Sudden Hearing Loss: Physicians should advise patients to stop use of all PDE5 inhibitors, including KTX, and seek medical attention in the event of a sudden loss of vision in one or both eyes & sudden decrease or loss of hearing.

Alpha blockers and Antihypertensives: Physicians should discuss with patients the potential for KTX to augment the blood-pressure-lowering effect of alpha blockers and antihypertensive medications. Caution is advised when PDE5 inhibitors are coadministered with alpha blockers Renal Insufficiency, Hepatic Impairment, Consumption of alcohol.

Food Interaction

• Avoid excessive or chronic alcohol consumption. Ingesting excess amounts of alcohol (more than four drinks in a short time) may potentiate the hypotension and dizziness caused by tadalafil.
• Avoid grapefruit products. KTX is metabolized by CYP3A4, and grapefruit products are CYP3A4 inhibitors; therefore, coadministration may increase serum levels of tadalafil and result in increased hypotension.
• Take with or without food.

[Moderate] GENERALLY AVOID: Additive hypotensive effects may occur when phosphodiesterase-5 (PDE5) inhibitors such as tadalafil are used with alcohol, as both are mild systemic vasodilators.

In clinical pharmacology studies, more subjects administered alcohol at a dose of 0.7 g

There were reports of postural dizziness, and orthostatic hypotension was observed in some.

When tadalafil 20 mg was administered with alcohol at a lower dose of 0.6 g

Neither tadalafil nor alcohol affected the plasma concentrations of the other.

GENERALLY AVOID: Coadministration with grapefruit juice is likely to increase the plasma concentrations of tadalafil, which is primarily metabolized by CYP450 3A4.

However, the interaction has not been studied.

The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit.

MANAGEMENT: Patients taking tadalafil should avoid consuming large amounts of alcohol, which may increase the potential for orthostatic signs and symptoms including increase in heart rate, decrease in standing blood pressure, dizziness, and headache.

It may also be appropriate to avoid consuming large amounts of grapefruit juice.

KTX Drug Interaction

Major: sildenafilMinor: tamsulosin, metoprolol, metoprololUnknown: aspirin, aspirin, ubiquinone, rosuvastatin, duloxetine, apixaban, omega-3 polyunsaturated fatty acids, fluticasone nasal, atorvastatin, pregabalin, acetaminophen, cyanocobalamin, ascorbic acid, cholecalciferol, rivaroxaban, cetirizine

KTX Disease Interaction

Major: cardiovascular disease, renal dysfunction, pulmonary diseaseModerate: priapism, alcoholism, hearing loss, liver disease, retinitis pigmentosa, seizure disorders

Volume of Distribution

• 63 L

Elimination Route

After single oral-dose administration, the maximum observed plasma concentration (Cmax) of tadalafil is achieved between 30 minutes and 6 hours (median time of 2 hours). Absolute bioavailability of tadalafil following oral dosing has not been determined.

Half Life

17.5 hours

Clearance

• oral cl=2.5 L/hr

Elimination Route

KTX is excreted predominantly as metabolites, mainly in the feces (approximately 61% of the dose) and to a lesser extent in the urine (approximately 36% of the dose).

Pregnancy & Breastfeeding use

It is not indicated for use in newborn, children or women.

Contraindication

Nitrates: Administration of tadalafil to patients who are using any form of organic nitrate, either regularly and/or intermittently, is contraindicated. In clinical pharmacology studies, tadalafil was shown to potentiate the hypotensive effect of nitrates.

Hypersensitivity Reactions: KTX is contraindicated in patients with a known serious hypersensitivity to tadalafil. Hypersensitivity reactions have been reported, including Stevens-Johnson syndrome and exfoliative dermatitis.

Special Warning

Renal Insufficiency-

For Use as Needed:

• Mild (creatinine clearance 51 to 80 mL/min): No dose adjustment is required.
• Moderate (creatinine clearance 31 to 50 mL/min): A starting dose of 5 mg not more than once per day is recommended, and the,maximum dose should be limited to 10 mg not more than once in every 48 hours.
• Severe (creatinine clearance <30 mL/min and on hemodialysis): The maximum recommended dose is 5 mg not more than once in every 72 hours.

For Once Daily Use:

• Mild (creatinine clearance 51 to 80 mL/min): No dose adjustment is required. Moderate (creatinine clearance 31 to 50 mL/min): No dose adjustment is required.
• Severe (creatinine clearance <30 mL/min and on hemodialysis): KTX for once daily use is not recommended.

Hepatic Impairment-

For Use as Needed:

• Mild or moderate: The dose should not exceed 10 mg once per day.
• Severe: Not recommended

For Once Daily Use:

• Mild or moderate: KTX for once daily use has not been extensively evaluated in patients with hepatic insufficiency. Therefore, caution is advised if KTX for once daily use is prescribed to these patients.
• Severe: Not recommended.

Geriatrics:

No dose adjustment is required in patients >65 years of age

Acute Overdose

Adverse events were similar to those seen at lower doses. In case of overdose, standard supportive measure should be adopted as required

Storage Condition

Store below 30° C. Protect from light and moisture. Keep out of reach of children.

Innovators Monograph

You find simplified version here KTX