effect of silodosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.trandolaprilMonitor Closely (1)trandolapril, silodosin. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Exaggerated first dose hypotensive response.trazodoneMonitor Closely (1)trazodone will decrease the level or effect of silodosin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.treprostinilMinor (1)treprostinil increases effects of silodosin by pharmacodynamic synergism. Minor/Significance Unknown.triamcinolone acetonide injectable suspensionSerious - Use Alternative (1)triamcinolone acetonide injectable suspension will decrease the level or effect of silodosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.tucatinibMonitor Closely (1)tucatinib will increase the level or effect of silodosin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. Consider reducing the dosage of P-gp substrates, where minimal concentration changes may lead to serious or life-threatening toxicities.vardenafilSerious - Use Alternative (1)vardenafil increases effects of silodosin by pharmacodynamic synergism. Contraindicated. Risk of hypotension.vemurafenibMonitor Closely (1)vemurafenib increases levels of silodosin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.verapamilMonitor Closely (2)verapamil will increase the level or effect of silodosin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. silodosin and verapamil both increase anti-hypertensive channel blocking. Use Caution/Monitor.Serious - Use Alternative (1)verapamil will increase the level or effect of silodosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated.voriconazoleSerious - Use Alternative (1)voriconazole will increase the level or effect of silodosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated.yohimbeSerious - Use Alternative (1)yohimbe increases effects of silodosin by pharmacodynamic synergism. Contraindicated.zafirlukastSerious - Use Alternative (1)zafirlukast will increase the level or effect of silodosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.zotepineMonitor Closely (1)silodosin and zotepine both increase anti-hypertensive channel blocking. Use Caution/Monitor. >10% Retrograde ejaculation (28%) 1-10% Diarrhea (3%) Headache (2%) Insomnia ((1-2%) Dizziness (3%) Orthostatic hypotension (3%; increased in patients >65 years) Nasopharyngitis (2%) Nasal congestion (2%) Sinusitis (1-2%) Postmarketing Reports Skin and subcutaneous tissue disorders: Toxic skin eruption, purpura, skin rash, pruritus, urticaria Hepatobiliary disorders: Jaundice, impaired hepatic function associated with increased transaminase values Immune system disorders: Allergic-type reactions, not limited to skin reactions including angioedema Genitourinary system: Priapism Contraindications Hypersensitivity Severe renal impairment (CrCl <30 mL/min) Severe hepatic impairment (Child-Pugh Score >10) Concomitant strong CYP3A4 inhibitors or P-glycoprotein inhibitors Cautions Use with caution in the elderly (risk of hypotension) Not indicated for use in women or children Not for use as hypertensive Postural hypotension, with or without symptoms (eg, dizziness) may develop when initiating treatment; there is potential for syncope; patients should be cautioned about driving, operating machinery, or performing hazardous tasks when initiating therapy Dose should be reduced to 4 mg in patients with moderate renal impairment; exercise caution and monitor such patients for adverse events Not tested in patients with severe hepatic impairment, and therefore, should not be prescribed to such patients; use with caution in patients with mid-to-moderate hepatic impairment Patients planning cataract surgery should be told to inform their ophthalmologist that they are receiving this therapy; intraoperative floppy iris syndrome observed during cataract surgery in some patients on alpha-1 blockers or previously treated with alpha-1 blockers; variant of small pupil syndrome is characterized by combination of a flaccid iris that billows in response to intraoperative irrigation currents; progressive intraoperative miosis despite preoperative dilation with standard mydriatic drugs; and potential prolapse of iris toward phacoemulsification incisions Carcinoma of prostate and BPH cause many of same symptoms; these two diseases frequently co-exist; patients thought to have BPH should be examined prior to starting therapy to rule out the presence of carcinoma of the prostate Drug interaction overview The pharmacodynamic interactions between silodosin and other alpha-blockers have not been determined; drug should not be used in combination with other alpha-blockers Specific pharmacodynamic interaction study between this drug and antihypertensive agents not performed; patients in Phase 3 clinical studies taking concomitant antihypertensive medications did not experience a significant increase in incidence of syncope, dizziness, or orthostasis; exercise caution during concomitant use with antihypertensives and monitor patients for possible adverse events Caution also advised when alpha-adrenergic blocking agents are coadministered with PDE5 inhibitors; alpha-adrenergic blockers and PDE5 inhibitors are both vasodilators that can lower blood pressure; concomitant use of two drug classes can potentially cause symptomatic hypotension Pregnancy Therapy is not indicated for use in females Infertility Males: Possible effects on male fertility could be observed based on findings in rats at exposures that were at least two times higher than at the MRHD (based on AUC); these findings may be reversible; clinical relevance unknown Lactation Therapy is not indicated for use in femalesPregnancy Categories A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk. B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available. Mechanism of Action Selective antagonist of postsynaptic alpha-1-adrenoceptors; blocking the alpha1A-adrenoreceptors in the smooth muscle of the prostate leads to relaxation of the smooth muscle in the bladder neck and prostate causing an improvement of urine flow and decreased symptom of BPH. Pharmacokinetics Time: 2.6 +/- 0.9 hr Concentration: (8mg dose) 62 ng/mL Bioavailability: 32% Half-Life: 13 +/- 8 hr Protein Bound: 97% Vd: 49.5 L Clearance: 10 L/hr Metabolism: glucuronidation, alcohol & aldehyde dehydrogenase, CYP3A4 Excretion: feces & urine BRAND FORM. UNIT PRICE PILL IMAGE silodosin oral- 4 mg capsulesilodosin oral- 8 mg capsulesilodosin oral- 8 mg capsulesilodosin oral- 4 mg capsulesilodosin oral- 8 mg capsulesilodosin oral- 8 mg capsulesilodosin oral- 4 mg capsulesilodosin oral- 8 mg capsulesilodosin oral- 4 mg capsulesilodosin oral- 4 mg capsuleRapaflo oral- 8 mg capsuleRapaflo oral- 4 mg capsuleCopyright © 2010 First DataBank, Inc.Print Patient Educationsilodosin oral SILODOSIN - ORAL (sye-LOE-doe-sin) COMMON BRAND NAME(S): Rapaflo USES: Silodosin is used by men to treat the symptoms of an enlarged prostate (benign prostatic hyperplasia-BPH). It does not shrink the prostate, but it works by relaxing the muscles in the prostate and the bladder. This helps to relieve symptoms of BPH such as difficulty in beginning the flow of urine, weak stream, and the need to urinate often or urgently (including during the middle of the night).Silodosin belongs to a class of drugs known as alpha blockers.Do not use this medication to treat high blood pressure. HOW TO USE: Take this medication by mouth as directed by your doctor, usually once daily with a meal.If you have difficulty swallowing this medication whole, you may sprinkle the entire contents of a capsule on a small amount (such as a tablespoon) of cool soft applesauce just before taking. Swallow the mixture right away (within 5 minutes). Do not chew the mixture, and do not save it for future use. Do not use hot applesauce. Drink a glass of cool water after each dose.Silodosin may cause a sudden drop in your blood pressure, which could lead to dizziness or fainting. This risk is higher when you first start taking this drug, after your doctor increases your dose, or if you restart treatment after you stop taking it. During these times, avoid situations where you may be injured if you faint.To avoid injury from dizziness or fainting, your doctor may tell you to take your first dose of silodosin with food at bedtime so that your body can get used to its effects.The dosage is based on your medical condition and response to treatment.Take this medication regularly to get the most benefit from it. To help you remember, take it with the same meal each day.Tell your doctor if your condition does not improve or if it worsens. SIDE EFFECTS: Dizziness, lightheadedness, or ejaculation problems may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.Tell your doctor right away if you have any serious side effects, including: fainting.Rarely, males may have a painful or prolonged erection lasting 4 or more hours. If this occurs, stop using this drug and get medical help right away, or permanent problems could occur.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345. PRECAUTIONS: Before taking silodosin, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney disease, liver disease, low blood pressure, certain eye problems (cataracts, glaucoma).This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).Before having surgery (including cataract/glaucoma eye surgery), tell your doctor or dentist if you are taking or have ever taken this medication, and about all the other products you use (including prescription drugs, nonprescription drugs, and herbal products).Older adults may be more sensitive to the side effects of this drug, especially dizziness and low blood pressure when getting up from a sitting or lying position. These side effects can increase the risk of falling.During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.It is unknown if this medication passes into breast milk. Consult your doctor before breast-feeding. DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.Some products that may interact with this drug include: other alpha blocker drugs (such as prazosin, terazosin).If you are also taking a drug to treat erectile dysfunction-ED or pulmonary hypertension (such as sildenafil, tadalafil), your blood pressure may get too low which can lead to dizziness or fainting. Your doctor may need to adjust your medications to minimize this risk.Other medications can affect the removal of silodosin from your body, which may affect how silodosin works. Examples include azole antifungals (such as itraconazole, ketoconazole), clarithromycin, cobicistat, cyclosporine, HIV protease inhibitors (such as lopinavir), mifepristone, ribociclib, ritonavir, among others. OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe dizziness, fainting. NOTES: Do not share this medication with others.Lab and/or medical tests (such as prostate exams, blood pressure) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details. MISSED DOSE: If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up. STORAGE: Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away