Aricept Consumer Drug Information and Facts

The purpose of this medication
Aricept is one of a group of drugs called "cholinesterase inhibitors" which is used to treat symptoms in people with mild to moderate Alzheimer Disease.

In brains of people with Alzheimer Disease there is a progressive degeneration of nerve cells. Particularly notable is a degeneration of cells which make acetylcholine, a chemical thought to be important for learning and memory. People with Alzheimer Disease have lower brain levels of acetylcholine. Aricept acts by decreasing the activity of acetylcholinesterase, an enzyme whose function is to break down acetylcholine. It is believed that by reducing the breakdown of acetylcholine, it will lead to an increase in the level of acetylcholine in the brain. The potential beneficial effect could lessen as the disease progresses and when fewer cells are available to make acetylcholine.

How to use aricept?

DRUG CLASS AND MECHANISM: Donepezil is an oral medication used to treat Alzheimer's disease. It belongs to a class of drugs called cholinesterase inhibitors that also includes tacrine (Cognex). Scientists believe that Alzheimer's disease may result from a deficiency in chemicals (neurotransmitters) used by nerves in the brain to communicate with one another. Donepezil inhibits acetylcholinesterase, an enzyme responsible for the destruction of one neurotransmitter, acetylcholine. This leads to increased concentrations of acetylcholine in the brain, and the increased concentrations are believed to be responsible for the improvement seen during treatment with donepezil. Donepezil improves the symptoms but does not slow down the progression of Alzheimer's disease. Donepezil was approved by the FDA in 1996.

PRESCRIPTION: yes

GENERIC AVAILABLE: no

PREPARATIONS: Aricept is available in 5 and 10 mg tablets. Aricept ODT (orally disintegrating tablets) also are available in 5 and 10 mg tablets.

STORAGE: Tablets should be stored at room temperature, 15-30°C (59-86°F).

PRESCRIBED FOR: Donepezil is used for the treatment of mild to moderate dementia of the Alzheimer's type.

DOSING: Donepezil is generally taken once daily at night prior to retiring. Its absorption is not affected by food so that it may be taken with or without food.

DRUG INTERACTIONS: Drugs with anti-cholinergic properties that can cross into the brain, such as atropine, benztropine (Cogentin), and trihexyphenidyl (Artane) counteract the effects of donepezil and should be avoided during therapy with donepezil.

Donepezil is metabolized (eliminated) by enzymes in the liver. The rate of metabolism of donepezil may be increased by medications that increase the amounts of these enzymes, such as carbamazepine (Tegretol), dexamethasone (Decadron), phenobarbital, phenytoin (Dilantin), and rifampin (Rifadin). By increasing elimination, these drugs may reduce the effects of donepezil.

Ketoconazole (Nizoral) has been shown to block the enzymes in the liver that metabolize donepezil. Therefore, concurrent use of ketoconazole and donepezil may result in increased concentrations of donepezil in the body and possibly lead to donepezil side effects. Quinidine (Quinidex, Quinaglute) also has been shown to inhibit the enzymes that metabolize donepezil and may cause donepezil side effects.

PREGNANCY: It is not known whether donepezil is harmful to the fetus. Safe use during pregnancy has not been established.

NURSING MOTHERS: It is not known whether the donepezil is secreted into breast milk or if breast-feeding while taking donepezil is safe for the nursing infant.

SIDE EFFECTS: The most frequently reported side effects associated with donepezil include headache, generalized pain, fatigue, dizziness, nausea, vomiting, diarrhea, loss of appetite, weight loss, muscle cramping, joint pain, insomnia, and increased frequency of urination.

DOSAGE AND ADMINISTRATION

The dosages of ARICEPT® shown to be effective in controlled clinical trials are 5 mg and 10 mg administered once per day.

The higher dose of 10 mg did not provide a statistically significantly greater clinical benefit than 5 mg. There is a suggestion, however, based upon order of group mean scores and dose trend analyses of data from these clinical trials, that a daily dose of 10 mg of ARICEPT® might provide additional benefit for some patients. Accordingly, whether or not to employ a dose of 10 mg is a matter of prescriber and patient preference.

Evidence from the controlled trials indicates that the 10 mg dose, with a one week titration, is likely to be associated with a higher incidence of cholinergic adverse events than the 5 mg dose. In open label trials using a 6 week titration, the frequency of these same adverse events was similar between the 5 mg and 10 mg dose groups. Therefore, because steady state is not achieved for 15 days and because the incidence of untoward effects may be influenced by the rate of dose escalation, treatment with a dose of 10 mg should not be contemplated until patients have been on a daily dose of 5 mg for 4 to 6 weeks.

How does it help?

Aricept is intended to treat symptoms in people with mild to moderate Alzheimer Disease. In clinical trials, individuals who took the drug when compared to individuals who took a placebo (a substance which looks like the drug but has no effect), showed improvement or no further decline in cognition (including memory, orientation, language) and function (including performance of daily activities).

The medication may take as long as 12 weeks to begin working, and the type and length of response to this medication will vary from person to person.

Important! Things to know before taking this medication

You should tell the doctor if you are allergic to donepezil hydrochloride or piperidine derivatives such as Mycobutin (rifabutin), Ritalin (methylphenidate), Akineton (biperiden HCI), Artane (trihexyphenidyl HCI), Bupivacaine HCI, and Paxil (paroxetine HCI). You should also tell your doctor if you have a condition affecting your heart or your lungs; if you have had seizures; if you have had fainting spells; and if you have a history of peptic ulcers or have an increased risk of developing ulcers (for example, if you are taking non-steroidal anti-inflammatory drugs [NSAIDs] or high doses of acetylsalicylic acid [ASA/Aspirin]). Aricept should not be used if you are pregnant or breastfeeding.

What are the possible side effects?

Along with its beneficial effect, Aricept may cause some undesirable reactions. The most common side effects include nausea, diarrhea, insomnia, vomiting, muscle cramps, fatigue and loss of appetite. In clinical studies these effects were often mild, and generally went away with continued treatment. In clinical studies some people treated with the drug experienced fainting. If you feel unwell in any other way or have any symptoms that you do not understand, or find distressing, you should contact your doctor immediately.

What to do if an overdose is taken ?

If more medication has been taken than what has been prescribed, contact your doctor, hospital emergency department, or the nearest poison control centre immediately.

How do you store this medication?

Aricept tablets contain donepezil hydrochloride. The 5 mg tablets are white and the 10 mg tablets are yellow.

Keep this medication in a safe place, out of reach of children.
Keep this medication in a cool dry place (15° to 30°C) and avoid exposure to moisture.
If the doctor decides to stop the treatment, return any leftover medication to your pharmacist. Keep it only if the doctor tells you to do so.