Cialis 20mg

1. Product Overview
Brand Name: Cialis®
Generic Name: Tadalafil
Dosage Strength: 20mg per tablet
Drug Class: Phosphodiesterase-5 (PDE5) inhibitor
Manufacturer: Eli Lilly and Company

2. Therapeutic Indications

• Primary: Treatment of erectile dysfunction (ED) in adult males

• Secondary: Management of benign prostatic hyperplasia (BPH) symptoms

• Combination therapy for concurrent ED and BPH

3. Pharmacological Properties

• Mechanism: Selective inhibition of PDE5 enzyme

• Onset of Action: As early as 30 minutes post-dose

• Duration: Effective for up to 36 hours

• Bioavailability: Approximately 15%

• Protein Binding: 94% (primarily to albumin)

• Metabolism: Hepatic (primarily via CYP3A4)

• Excretion: Feces (61%) and urine (36%)

4. Recommended Dosage

• Standard ED Treatment: 20mg taken prior to anticipated sexual activity

• Maximum Frequency: Once daily

• Administration Guidelines:

  • Take with a full glass of water

  • May be taken with or without food

  • Avoid high-fat meals which may delay absorption

  • Optimal timing: 30-60 minutes before sexual activity

5. Clinical Efficacy

• Demonstrated success rate: 67-81% in clinical trials

• Improved erection maintenance in:

  • 81% of general ED population

  • 64% of diabetic ED patients

  • 72% of post-prostatectomy patients

6. Contraindications

• Absolute:

  • Concomitant nitrate therapy

  • Hypersensitivity to tadalafil

• Relative:

  • Unstable angina

  • Recent myocardial infarction

  • Severe hepatic impairment

  • Severe cardiovascular disease

7. Warnings & Precautions

• Cardiovascular:

  • Not for use in patients with cardiac conditions where sexual activity is inadvisable

  • Potential for mild, transient decreases in blood pressure

• Ophthalmic:

  • Risk of NAION (non-arteritic anterior ischemic optic neuropathy)

  • Potential for sudden hearing loss

• Priapism:

  • Risk of prolonged erection (>4 hours)

  • Emergency treatment required to prevent permanent damage

8. Adverse Effects
Common (≥2% incidence):

• Headache (15%)

• Dyspepsia (10%)

• Back pain/myalgia (6-9%)

• Nasal congestion (4%)

• Flushing (3%)

Serious (require immediate medical attention):

• Sudden vision loss

• Hearing impairment

• Cardiovascular events

• Priapism

9. Drug Interactions
Major Interactions:

• Nitrates: Severe hypotension (absolute contraindication)

• Alpha-blockers: Additive hypotensive effects

• CYP3A4 inhibitors: Increased tadalafil exposure

• CYP3A4 inducers: Decreased tadalafil efficacy

10. Special Populations

• Elderly: Consider lower starting dose

• Renal Impairment:

  • Moderate (CrCl 30-50 mL/min): Max 10mg

  • Severe (CrCl <30 mL/min): Not recommended

• Hepatic Impairment:

  • Moderate-severe: Max 10mg

  • Severe cirrhosis: Avoid use

11. Patient Counseling Points

• Sexual stimulation required for effect

• Avoid nitrate-containing medications

• Seek immediate care for erections >4 hours

• Report vision/hearing changes promptly

• Alcohol may increase side effects

• Does not protect against STDs

12. Storage & Handling

• Storage Conditions: 20-25°C (68-77°F)

• Protection: Keep in original blister packaging

• Shelf Life: 24 months from manufacture date

• Disposal: Follow local medication disposal guidelines

13. Presentation & Packaging

• Tablet Characteristics:

  • Yellow, almond-shaped

  • Film-coated

  • “C20” imprint

• Available Pack Sizes:

  • 4 tablets

  • 8 tablets

  • 12 tablets

  • 30 tablets (for daily dosing regimen)

14. Regulatory Status

• Prescription-only medication

• Approved by:

  • FDA (2003)

  • EMA (2002)

  • Other major regulatory bodies worldwide

15. Clinical Pharmacology

• Peak Plasma Concentration: 2 hours (range 0.5-6 hours)

• Elimination Half-life: 17.5 hours

• Steady State: Achieved within 5 days

• Food Effect: High-fat meal may delay Tmax by 1 hour