Flomax Vs. Viagra: Drug Comparison

Flomax^® (tamsulosin hydrochloride) is a medication commonly prescribed to treat benign prostatic hyperplasia (BPH), a condition characterized by an enlarged prostate. It works by relaxing the muscles in the prostate and bladder neck, making it easier to urinate and relieving symptoms such as difficulty starting urination, weak stream, and the need to urinate frequently or urgently. Flomax is typically taken once daily, about 30 minutes after the same meal each day. Common side effects include dizziness, runny nose, and ejaculation problems. Flomax should be used with caution in patients with a history of low blood pressure.

Viagra^® (sildenafil citrate), a phosphodiesterase type 5 (PDE5) inhibitor, is an oral medication used to treat erectile dysfunction (ED). It is taken only as needed, usually about an hour before sexual activity, though it can be effective if taken between 30 minutes to 4 hours prior. It is very important not to take Viagra more than once a day, as exceeding this frequency increases the risk of serious side effects, including vision loss and significant drops in blood pressure.

Alpha-1 adrenoceptor antagonist

Phosphodiesterase-5 (PDE5) inhibitor

Flomax (tamsulosin hydrochloride) is indicated to treat:

• The signs and symptoms of benign prostatic hyperplasia (BPH)

Viagra (sildenafil citrate) is indicated to treat:

• Erectile dysfunction (ED)

• Typically taken orally once daily

• Comes in 0.4 mg capsules

• Typically taken orally as needed approximately 60 minutes before sexual activity, up to once daily

• Comes in 25 mg, 50 mg, and 100 mg tablets

The most common adverse events (≥2% of patients and at a higher incidence than placebo) with the 0.4 mg dose or 0.8 mg dose were:

• Headache

• Dizziness

• Nasal congestion

• Infection

• Abnormal ejaculation

• Weakness

• Back pain

• Diarrhea

• Sore throat

• Chest pain

• Cough increased

• Somnolence

• Nausea

• Inflammation of the sinuses

• Insomnia

• Libido decreased

• Tooth disorder

• Blurred vision

Most common adverse reactions (≥2%) include:

• Headache

• Flushing

• Indigestion

• Abnormal vision

• Nasal congestion

• Back pain

• Muscle pain

• Nausea

• Dizziness

• Rash

• Contraindicated in patients known to be hypersensitive to tamsulosin hydrochloride or any component of Flomax capsules

• Drug interactions: Strong inhibitors of CYP3A4 (e.g., ketoconazole), moderate inhibitors of CYP3A4 (e.g., erythromycin), strong (e.g., paroxetine) or moderate (e.g., terbinafine) inhibitors of CYP2D6, patients known to be CYP2D6 poor metabolizers, PDE5 inhibitors

• Administration of Viagra to patients using nitric oxide donors, such as organic nitrates or organic nitrites in any form

• Known hypersensitivity to sildenafil or any component of tablet

• Drug interactions: Nitrates, alpha blockers, antihypertensives, CYP3A4 inhibitors (e.g., ritonavir, ketoconazole, itraconazole, saquinavir, erythromycin)

• Postural low blood pressure

• Should not be used in combination with strong inhibitors of CYP3A4. Use with caution in combination with moderate inhibitors of CYP3A4, with strong or moderate inhibitors of CYP2D6, in patients known to be CYP2D6 poor metabolizers, or in combination with other cytochrome P450 inhibitors

• Should not be used in combination with other alpha adrenergic blocking agents

• Exercise caution with concomitant administration of warfarin

• Possibility of prolonged erection

• Intraoperative floppy iris syndrome has been observed during cataract and glaucoma surgery in some patients

• Be screened for the presence of prostate cancer prior to treatment and at regular intervals afterwards

• Patients should not use Viagra if sexual activity is inadvisable due to cardiovascular status

• Patients should seek emergency treatment if an erection lasts >4 hours

• Patients should stop Viagra and seek medical care if a sudden loss of vision occurs in one or both eyes, which could be a sign of non arteritic anterior ischemic optic neuropathy (NAION)

• Patients should stop Viagra and seek prompt medical attention in the event of sudden decrease or loss of hearing

• Caution is advised when Viagra is co-administered with alpha-blockers or anti-hypertensives

• Decreased blood pressure, fainting, and prolonged erection may occur at higher sildenafil exposures

*This information is from the label for brand name Flomax^®. See the Full Prescribing Information for more complete information. Tamsulosin, the active ingredient in Flomax, may also be the active ingredient in other medications, and this information may not be accurate for all medications that include the active ingredient tamsulosin.

*This information is from the label for brand name Viagra^®. See the Full Prescribing Information for more complete information. Sildenafil, the active ingredient in Viagra, may also be the active ingredient in other medications, and this information may not be accurate for all medications that include the active ingredient sildenafil.