Darifenacin belongs to the family of medications known as antimuscarinics. It is used to relieve symptoms associated with an overactive bladder, such as urinary urgency (a need to urinate right away), urinary frequency, increased urination at night, and urge incontinence (leaking or wetting caused by an unstoppable urge to urinate).

The medication works by reducing abnormal bladder contractions. It helps to reduce bladder spasms, the urge to pass urine, and the frequency of urination.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

The recommended initial dose of darifenacin is 7.5 mg taken once daily at the same time every day. The dose can be increased to 15 mg daily, 2 weeks after starting treatment if needed.

For people with moderate liver function impairment, or for those taking certain medications (e.g., clarithromycin, ketoconazole, itraconazole, miconazole, nefazodone), doses above 7.5 mg daily are not recommended.

Darifenacin should be taken with liquids and swallowed whole. The tablets should not be chewed, divided, or crushed. This medication may be taken with or without food.

Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light, and keep it out of the reach of children.

7.5 mg
Each white, round, biconvex, film-coated tablet, engraved with “APO” on one side and “DA” over “7.5” on the other side, contains 7.5 mg of darifenacin as darifenacin hydrobromide. Nonmedicinal ingredients: anhydrous dibasic calcium phosphate, colloidal silicon dioxide, hypromellose, magnesium stearate, polyvinyl alcohol, polyethylene glycol, talc, and titanium dioxide.

15 mg
Each orange, round, biconvex, film-coated tablet, engraved with “APO” on one side and “DA” over “15” on the other side, contains 15 mg of darifenacin as darifenacin hydrobromide. Nonmedicinal ingredients: anhydrous dibasic calcium phosphate, colloidal silicon dioxide, Euroxide red iron oxide, hypromellose, magnesium stearate, polyvinyl alcohol, polyethylene glycol, talc, titanium dioxide, and yellow iron oxide.

Do not take darifenacin if you:

• are allergic to darifenacin or to any of the ingredients of the medication
• have or are at risk for gastric retention (delayed emptying of the stomach)
• have or are at risk for urinary retention (an inability to empty the bladder)
• have uncontrolled narrow-angle glaucoma
• have severe constipation (2 or fewer bowel movements per week)

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent. The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• abdominal pain
• changed sense of taste
• constipation
• cough
• decreased sexual ability
• diarrhea
• dizziness
• dry eyes or nose
• dry mouth
• gas
• headache
• heartburn
• itching
• mouth irritation
• nausea
• runny or stuffy nose
• skin rash
• sweating
• trouble sleeping
• unusual weakness

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• accidental injury
• facial swelling
• increased blood pressure
• overall swelling
• shortness of breath
• signs of a urinary tract infection (e.g., difficult or painful urination, or blood in the urine)
• swelling of the feet, ankles, or lower leg
• vaginal discharge and itching
• vision changes

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)
• sudden inability to urinate, bladder pain, or abdominal pain

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Bladder outflow obstruction: If you have a medical problem that obstructs the flow of urine from the bladder (e.g., enlarged prostate, prostate cancer), this medication may make you unable to urinate. Talk to your doctor about the risks and benefits of using this medication. People with a history of bladder outflow obstruction should discuss with their doctor how this medication may affect their medical condition, how their medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Dizziness/blurred vision: Darifenacin may cause dizziness or blurred vision. Avoid activities such as driving, operating machinery, or performing hazardous work until you know how darifenacin affects you.

Gastrointestinal disorders: Because of the risk of intestinal blockage, your doctor should closely monitor your condition if you have:

• decreased gastrointestinal movement caused by medical problems (e.g., diabetes), surgery, or medications;
• a medical problem that obstructs the gastrointestinal tract (e.g., pyloric stenosis); or
• severe constipation (2 or fewer bowel movements per week)

If you have a history of a gastrointestinal disorder of this sort, you should discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Glaucoma: Darifenacin may make the symptoms of narrow-angle glaucoma worse. If you have narrow-angle glaucoma, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Liver function: Decreased liver function or liver disease can cause this medication to build up in the body, causing side effects. If you have moderate liver function impairment, you should not take daily doses greater than 7.5 mg of darifenacin. Darifenacin is not recommended for people with severe liver function impairment. If you have a history of liver disease or reduced liver function, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: It is not known if darifenacin passes into breast milk. If you are breast-feeding and taking darifenacin, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

There may be an interaction between darifenacin and any of the following:

• acetylcholinesterase inhibitors (e.g., donepezil, galantamine, rivastigmine)
• aclidinium
• amantadine
• amphetamines (e.g., dextroamphetamine, lisdexamfetamine)
• antiarrhythmics (e.g., disopyramide, dronedarone, flecainide, propafenone)
• antihistamines (e.g., bilastine, cetirizine, diphenhydramine, doxylamine, loratadine, rupatadine)
• antipsychotics (e.g., aripiprazole, chlorpromazine, clozapine, haloperidol, quetiapine, risperidone)
• aprepitant
• atomoxetine
• atropine
• "azole" antifungals (e.g., fluconazole, itraconazole, ketoconazole)
• benztropine
• beta-blockers (e.g., carvedilol, metoprolol, propranolol, timolol)
• bosentan
• botulinum-toxin containing medications
• buprenorphine
• butorphanol
• calcium channel blockers (e.g., diltiazem, verapamil)
• cannabis
• chloral hydrate
• clidinium
• cobicistat
• cyclobenzaprine
• dextromethorphan
• dimenhydrinate
• domperidone
• eliglustat
• ethopropazine
• fesoterodine
• glucagon
• glycopyrrolate
• glycopyrronium
• grapefruit juice
• HIV protease inhibitors (e.g., darunavir, lopinavir, tipranavir)
• ipratropium
• ketotifen
• lenacapavir
• letermovir
• lumacaftor and ivacaftor
• macrolide antibiotics (e.g., clarithromycin, erythromycin)
• methadone
• metoclopramide
• mifepristone
• mirabegron
• monoamine oxidase inhibitors (e.g., moclobemide, phenelzine, tranylcypromine)
• nabilone
• narcotic medications (e.g., morphine, codeine, fentanyl, hydromorphone, oxycodone, tapentadol, tramadol)
• nirmatrelvir and ritonavir
• nitroglycerin
• olopatadine
• orphenadrine
• oxybutynin
• pitolisant
• pizotifen
• potassium supplements
• propiverine
• prucalopride
• selective serotonin reuptake inhibitors (SSRIs; e.g., paroxetine, vortioxetine)
• solifenacin
• tamoxifen
• tamsulosin
• tetrabenazine
• thiazide diuretics (e.g., hydrochlorothiazide, indapamide)
• tiotropium
• tolterodine
• topiramate
• tricyclic antidepressants (e.g., amitriptyline, clomipramine, imipramine, nortriptyline)
• trospium
• tyrosine kinase inhibitors (e.g., crizotinib, imatinib, nilotinib)
• umeclidinium

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any supplements you take. Since caffeine, decongestants, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.