EREC® (Sildenafil 100 mg) – Uses, Dosage, Side Effects, Precautions

MEDICAL INFORMATION: This medication is available only with a doctor’s prescription. This article is for educational purposes and is not a substitute for professional medical advice. Always consult a healthcare professional before using this product.

EREC® (Sildenafil 100 mg): Complete Medical Guide

Summary

EREC® is a film-coated tablet containing Sildenafil citrate, developed by ADWIA (Egypt). Sildenafil is a selective phosphodiesterase type 5 (PDE5) inhibitor used to treat erectile dysfunction (ED). It enhances erectile response by increasing blood flow to the penis in the presence of sexual stimulation.

Manufacturer

• Manufacturer: ADWIA Co. for Pharmaceuticals & Chemical Industries, 10th of Ramadan City, Egypt.

Category & Active Ingredient

• Category: Phosphodiesterase type 5 (PDE5) inhibitor.
• Active Ingredient: Sildenafil citrate (equivalent to 100 mg Sildenafil per tablet).

Available Forms & Strengths

• EREC® 100 mg film-coated tablets: Packs may contain 1, 2, or 4 tablets per strip; marketed in packs of 1, 3, 25, 50, or 100 strips.

Mechanism of Action

Sildenafil selectively inhibits phosphodiesterase type 5 (PDE5), an enzyme that degrades cyclic guanosine monophosphate (cGMP). By preventing cGMP breakdown, Sildenafil enhances nitric oxide–mediated vasodilation in the corpus cavernosum, leading to smooth muscle relaxation, increased penile blood flow, and an erection in response to sexual stimulation.

Indications

• Treatment of erectile dysfunction (ED) in adult men.

Dosage & Administration

• Standard Adult Dose: 50 mg taken orally about 30 minutes to 4 hours before sexual activity.
• Dose Adjustment: May be increased to 100 mg or reduced to 25 mg depending on efficacy and tolerability.
• Maximum Dose: Once daily.
• Special Populations: In elderly patients (>65 years), or those with hepatic impairment, severe renal impairment, or concomitant CYP3A4 inhibitors, start at 25 mg.
• Requirement: Sexual stimulation is necessary for efficacy.

Contraindications

• Concomitant use with nitrates (risk of severe hypotension).
• Patients advised against sexual activity due to cardiovascular status.
• Severe cardiovascular disorders (unstable angina, recent myocardial infarction, severe heart failure).
• Known hypersensitivity to Sildenafil or tablet components.
• Retinitis pigmentosa (rare hereditary retinal disorder).

Precautions

• Use with caution in patients with cardiovascular disease, anatomical penile deformities, or predisposition to priapism (e.g., sickle cell anemia, multiple myeloma, leukemia).
• Avoid in men with recent stroke, myocardial infarction, or life-threatening arrhythmia within the last 6 months.
• Not indicated for use in women or pediatric patients.
• Prolonged erection or priapism (>4 hours) requires immediate medical attention to prevent permanent damage.

Drug Interactions

• Nitrates: Contraindicated due to severe hypotension risk.
• Alpha-blockers: May cause symptomatic hypotension; use cautiously.
• CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, ritonavir, erythromycin, cimetidine) increase Sildenafil plasma levels.
• Rifampicin: Decreases Sildenafil plasma concentration.
• Alcohol: May increase risk of orthostatic hypotension.

Side Effects

• Common: Headache, flushing, nasal congestion, dizziness, dyspepsia, visual disturbances (blue-tinted vision, increased brightness sensitivity).
• Less common: Back pain, muscle aches, insomnia, rash.
• Serious (rare): Priapism, sudden hearing loss, myocardial infarction, stroke, severe hypotension, vision loss (NAION).

Warnings

• Do not exceed the maximum recommended dose.
• Use only under medical supervision, especially in patients with cardiovascular disease.
• Not protective against sexually transmitted infections (STIs).

Pharmacokinetics

• Absorption: Rapidly absorbed; peak plasma concentrations in 30–120 minutes (delayed by fatty meals).
• Bioavailability: Approximately 40%.
• Metabolism: Primarily by CYP3A4 (major) and CYP2C9 (minor).
• Half-life: ~4 hours.
• Elimination: Mainly feces (80%), urine (13%).

Storage

Store below 30°C, protected from direct sunlight, and out of reach of children.

Packaging

Boxes may contain 1, 3, 25, 50, or 100 strips. Each strip contains 1, 2, or 4 film-coated tablets.

Clinical Considerations

• Not for daily continuous use unless prescribed in special cases.
• Effectiveness depends on sexual stimulation.
• Caution in combining with antihypertensives due to additive blood pressure–lowering effect.

Frequently Asked Questions (FAQ)

How long does EREC® take to work?
Usually 30–60 minutes; sexual stimulation is required for effect.

Can I take EREC® every day?
It should not be used more than once daily. Continuous daily use is not generally recommended unless directed by a doctor.

Is EREC® safe with alcohol?
Alcohol may worsen dizziness and hypotension; avoid excessive intake when using Sildenafil.

What if I have diabetes or hypertension?
Sildenafil is often prescribed in such patients, but medical supervision is essential to prevent complications.

References

1. FDA Prescribing Information – Sildenafil
2. British National Formulary (BNF) – Sildenafil
3. ADWIA official product leaflet (EREC®).