DARIFENACIN (Systemic)?

Some commonly used brand names are:

In the U.S.?

• Enablex

? Not commercially available in Canada.

Category

• Antispasmodic (urinarybladder)

Description

Darifenacin (dar-i-FEN-a-cin)is used to treat bladder problems such as frequent need to urinate or lossof control of urinary function.

This medicine is available only with your doctor's prescription, in thefollowing dosage forms:

Oral
• Tablets (U.S.)

Before Using This Medicine

In deciding to use a medicine,the risks of using the medicine must be weighed against the good it will do.This is a decision you and your doctor will make. For darifenacin, the followingshould be considered:

Allergies?Tell your doctor if you have ever had any unusualor allergic reaction to darifenacin. Also tell your doctor and pharmacistif you are allergic to any other substances, such as foods, preservatives,or dyes.

Pregnancy?Darifenacin has not been studied in pregnant women.However, studies in animals have shown that darifenacin may cause unwantedeffects in the fetus. Before taking this medicine, make sure your doctor knowsif you are pregnant or if you may become pregnant.

Breast-feeding?It is not known whether darifenacin passes intobreast milk. However, darifenacin does pass into the milk of animals. Motherswho are taking this medicine and who wish to breast-feed should discuss thiswith their doctor.

Children?Studies on this medicine have been done only inadult patients, and there is no specific information comparing use of darifenacinin children with use in other age groups.

Older adults?This medicine has been tested and has not beenshown to cause different side effects or problems in older people than itdoes in younger adults.

Other medicines?Although certain medicines should not be usedtogether at all, in other cases two different medicines may be used togethereven if an interaction might occur. In these cases, your doctor may want tochange the dose, or other precautions may be necessary. When you are takingdarifenacin, it is especially important that your doctor and pharmacist knowif you are taking any of the following:

• CYP2D6 substrates such as
• Flecainide (e.g., Tambocor) or
• Imipramine (e.g., Tofranil) or
• Thioridazine (e.g., Mellaril) or
• Tricyclic antidepressants (antidepressant used to treat mental depression)?Effectsof these medicines may be increased

• CYP3A4 inhibitors such as
• Clarithromycin (e.g., Biaxin) or
• Itraconazole (e.g., Sporanox) or
• Ketoconazole (e.g., Nizoral) or
• Nefazoxone (e.g., Serzone) or
• Nelfinavir (e.g., Viracept) or
• Ritonavir (e.g., Norvir)?May increase the effects of darifenacin.

Other medical problems?The presence of other medicalproblems may affect the use of darifenacin. Make sure you tell your doctorif you have any other medical problems, especially:

• Glaucoma or
• Stomach problems or
• Urinary retention?You should not use darifenacin; it will makethese conditions worse.

• Liver problems?You should not use darifenacin if you have severeliver problems.

Proper Use of This Medicine

Dosing?The dose of darifenacin will be different for different patients. Follow your doctor's orders or the directions on thelabel. The following information includes only the average doses ofdarifenacin. If your dose is different, do not changeit unless your doctor tells you to do so.

• For oral dosage form (tablets):
  • To treat bladder problems:
    • Adults?7.5 milligrams (mg) once a day.
    • Children?Use and dose must be determined by your doctor.

Missed dose?If you miss a dose of this medicine, skip themissed dose and go back to your regular dosing schedule. Do not double doses.

Storage?

• Keep out of the reach of children.
• Do not store in the bathroom, near the kitchen sink, or in otherdamp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Ask yourhealth care professional how you should dispose of any medicine you do notuse. Be sure that any discarded medicine is out of the reach of children.

Precautions While Using This Medicine

This medicine may cause some people to have vision problems. Make sure your vision is clear before you drive or do anything else that couldbe dangerous if you are not able to see well.

Use caution during exercise or hot weather.Overheating may result in heat exhaustion.

This medicine may cause constipation, call your doctorif you get severe stomach pain or become constipated.

This medicine may cause dryness of the mouth. For temporary relief of mouthdryness, use sugarless candy or gum, melt bits of ice in your mouth, or usea saliva substitute. However, if your mouth continues to feel dry for morethan 2 weeks, check with your medical doctor or dentist.

Side Effects of This Medicine

Along with its needed effects, a medicinemay cause some unwanted effects. Although not all of these side effects mayoccur, if they do occur they may need medical attention.

Check with your doctorimmediately if any of the following side effects occur:

Frequency unknown

Decrease in frequency of urination; decrease in urine volume; difficulty in passing urine; dribbling, painful urination

Symptoms of overdose

Get emergency help immediately if any of the followingsymptoms of overdose occur

Changes in vision

Other side effects may occur that usuallydo not need medical attention. These side effects may go away during treatmentas your body adjusts to the medicine. However, check with your doctor if anyof the following side effects continue or are bothersome.

More common

Acid or sour stomach; belching; difficulty having a bowel movement (stool); dry mouth; heartburn; indigestion; stomach discomfort upset or pain

Less common

Bladder pain; bloody or cloudy urine; diarrhea; difficult, burning,or painful urination; dizziness; dry eyes; frequent urge to urinate; lack or loss of strength; lower backor side pain; nausea

Frequency unknown

Accidental injury; bloating or swellingof face, arms, hands, lower legs, or feet; blurredvision; changes in vision; chills; congestion; coughproducing mucus; difficulty breathing; difficulty in moving; dry skin; dryness or soreness of throat; fever; general feeling of discomfort or illness; headache; hoarseness; itching of the vagina or genital area; itching skin; joint pain; loss of appetite; muscle aches and pains; muscle pain or stiffness; nervousness; pain during sexual intercourse; painin joints; pain or tenderness around eyes and cheekbones; pounding in the ears; rash; runny nose; shortnessof breath or troubled breathing; slow or fast heartbeat; sneezing; stuffy nose ; tender, swollen glands in neck; thick, white vaginal discharge with no odor or with a mild odor; tightness in chest; tingling of handsor feet; trouble in swallowing; unusual weight gain or loss; voice changes; vomiting; wheezing

Other side effects not listed abovemay also occur in some patients. If you notice any other effects, check withyour doctor.