#bph agent

Brand Name: Flomax

Generic Available

Common Dosage Forms:

Capsules: 0.4 mg

FDA Indications/Dosages:

Treatment of the signs and symptoms of benign prostatic hyperplasia (BPH): Starting dose is usually one 0.4 mg capsule daily given one-half hour following the same meal every day. For patients who do not respond to 0.4 mg daily after 2-4 weeks, increase dose to 0.8 mg or 2 capsules daily given one-half hour following the same meal every day.

Pharmacology/Pharmacokinetics: Benign prostatic hyperplasia (BPH) is a condition that is commonly found in men over the age of 50 years. BPH is caused by a slow increase in the size of the prostate gland, a small gland that sits below the bladder and surrounds the bladder output, and by an increase in the smooth muscle tone in the prostate and bladder neck. Symptoms include a weak urinary stream, a delay upon urination, frequent urination, a feeling that the bladder cannot be emptied, and a feeling of immediate urination. Tamsulosin is a selective alpha-adrenergic blocking agent for receptors found in the prostate. Blockage of prostate alpha-adrenergic receptors relax the prostate gland and bladder neck and result in increased urinary flow and a reduction in the symptoms of BPH. Peak plasma levels are reached in 4-5 hours under fasting conditions. The presence of food decreases bioavailability. Between 94-99% is bound to plasma proteins but no pharmacokinetic changes were seen when given with other drugs bound to plasma proteins. Following metabolism in the liver by cytochrome P450 enzymes, 76% is excreted in the urine.

Drug Interactions: Additive effects may be seen when used with other alpha-adrenergic blocking agents. Strong inhibitors of CYP3A4 (cimetidine, ketoconazole) decreases clearance and raises plasma levels of tamsulosin.

Contraindications/Precautions: Contraindicated in patients with known hypersensitivity to tamsulosin. Patients should be tested initially to rule out prostate carcinoma and confirm the diagnosis of BPH. Orthostatic hypotension may occur during therapy therefore patients should be warned about possible syncope and dizziness. Tamsulosin should not be used with other alpha-adrenergic blocking agents or in combination with strong inhibitors of CYP3A4. Rare cases of priapism can occur during treatment. Intraoperative Floppy Iris Syndrome has been observed during cataract and glaucoma surgery. Patients should tell their ophthalmologist that they have taken tamsulosin. Pregnancy Category B.

Adverse Effects: Headache (19%), dizziness (15%), rhinitis (13%), infection (10%), asthenia (9%), abnormal ejaculation (8%), back pain (7%), pharyngitis (6%), diarrhea (6%), chest pains (4%), cough (3%), somnolence (3%), insomnia (2%), nausea (2%), sinusitis (2%), and PRIAPISM (<1%). Adverse effects are slightly higher when 0.8 mg/day is given.

Patient Consultation:

Take dose one-half hour following the same meal every day. If a dose is missed, skip it and return to normal dosing schedule.

May cause dizziness, especially when rising from the sitting position. Use caution when performing any hazardous task.

Store in a cool, dry place away from sunlight.

Do not discontinue or skip therapy without first consulting physician.

Brand Name: Proscar

Generic Available

Common Dosage Forms*:

Tablets: 5 mg

*Finasteride is also available as Propecia 1 mg for a different indication.

FDA Indications/Dosages:

Treatment of symptomatic benign prostatic hyperplasia: 5 mg given once a day. Therapy should continue for at least 6-12 months before analysis of treatment is performed. Clinical improvement manifested by an increase in urinary flow can be found in 60% of treated patients. Improvement in symptoms of BPH can be seen in >30% of treated patients.

To reduce the risk of symptomatic progression of benign hyperplasia: 5 mg given once a day with the alpha-blocker doxazosin.

Monitor: PSA

Pharmacology/Pharmacokinetics: Finasteride competitively inhibits the enzyme 5-alpha-reductase which is responsible for metabolizing testosterone to 5-alpha-dihydrotestosterone (DHT) in the prostate gland, liver, and skin. The development of the prostate gland is dependent on DHT. DHT levels are decreased in the blood and urine by up to 70% during treatment with finasteride. Peak plasma levels are reached in 1-2 hours with an elimination half-life of 6 hours. Approximately 90% is bound to plasma proteins. Excretion of metabolized drug occurs in the urine and feces.

Drug Interactions: May decrease theophylline levels.

Contraindications/Precautions: Contraindicated in women and children. Women who are or plan to become pregnant should not crushed finasteride tablets or be exposed to semen from a patient who is taking finasteride. Rule out other conditions, including infection, cancer, stricture disease, hypotonic bladder, and other neurogenic disorders, before initiating therapy. Finasteride decreases PSA levels in patients even in the presence of prostate cancer. PSA levels are used to determine whether the prostate is cancerous. Pregnancy Category X.

Adverse Effects: Possible adverse effects include depression, erectile dysfunction, decreased libido, and male infertility.

Patient Consultation:

Store in a cool, dry place away from sunlight and children.

Women who are or plan to become pregnant should not handle crushed finasteride tablets or be exposed to semen from a patient who is taking finasteride.

If a dose is missed, take it as soon as possible. If it is closer to the time of your next dose than the dose you missed, skip the missed dose and return to your dosing schedule.