tolterodine (Detrol)

Tolterodine belongs to a class of drugs called cholinergic (acetylcholine) receptor blockers. It is used to treat disorders of the urinary bladder that affect urination. The urinary bladder is a muscular "bag." Urine coming from the kidneys fills the bladder and causes it to stretch like a balloon. As it stretches, pressure in the bladder increases and, when the bladder reaches a certain level of stretch, a desire to urinate is felt. Nerves in the muscular wall of the bladder release acetylcholine, a chemical that attaches to receptors on the muscle cells and causes the cells to contract (tighten). This contributes further to the increase in pressure within the bladder and the desire to urinate. At the appropriate time (for example, when a toilet is available), there is conscious relaxation of the muscle at the outlet of the bladder, and the high bladder pressure forces urine out of the bladder. Normally, urination is under conscious control; however, in some individuals normal control as well as normal sensation are lost. The desire to urinate may be felt when there is little urine in the bladder, and urination may occur without warning or control. By blocking the effect of acetylcholine on the muscle cells, tolterodine slows the build-up of pressure in the bladder, reduces the sensation to urinate, and prevents uncontrolled urination. The FDA approved tolterodine in 1998. An extended release form of tolterodine, (Detrol LA) was approved by the FDA in 2001.

What brand names are available for tolterodine?

Detrol, Detrol LA

Is tolterodine available as a generic drug?

No

Do I need a prescription for tolterodine?

Yes

The most common side effects of tolterodine are:

• dry mouth,
• dry eyes,
• headache,
• upset stomach,
• dizziness,
• drowziness, and
• constipation.

Tolterodine also may cause blurred vision. Caution is recommended for patients with narrow-angle glaucoma, obstruction to the flow of urine, or poor emptying of the stomach since tolterodine may worsen these medical conditions.

Tolterodine usually is taken twice daily. The starting dose is 1 or 2 mg twice daily. The starting dose when using long-acting tolterodine is 2 or 4 mg daily. The dose may need to be reduced for patients who have impaired liver or kidney function.

Tolterodine is broken down by liver enzymes before elimination from the body. Drugs that block these liver enzymes may slow the elimination of tolterodine, raise tolterodine blood levels, and lead to side effects. The list of drugs that may interfere with the elimination of tolterodine includes erythromycin, clarithromycin (Biaxin), ketoconazole (Nizoral), itraconazole (Sporanox), cyclosporine, vinblastine, and miconazole (Monistat, Micatin). The dose of tolterodine should be reduced to 1 mg twice daily if taken with any of these drugs.

At doses much greater than those used in humans, tolterodine causes fetal abnormalities in animals, but there are no studies with tolterodine in pregnant women. Therefore, tolterodine should only be given to pregnant women if the benefits are felt to outweigh the potential risks.

Tolterodine is secreted into breast milk in animals; however, it is not known if tolterodine is secreted into the breast milk of women. Therefore, nursing mothers should either not breast feed or discontinue tolterodine.

What preparations of tolterodine are available?

Tablets: 1 and 2mg. Long acting capsules: 2 and 4 mg.

How should I keep tolterodine stored?

Tablets and capsules should be stored at room temperature, 15 C - 30 C (59 F - 86 F).