Tacrine is used to treat the symptoms of mild to moderate Alzheimer’s disease. Tacrine will not cure Alzheimer’s disease, and it will not stop the disease from getting worse. However, tacrine can improve thinking ability in some patients with Alzheimer’s disease.
In Alzheimer’s disease, many chemical changes take place in the brain. One of the earliest and biggest changes is that there is less of a chemical messenger called acetylcholine (ACh). ACh helps the brain to work properly. Tacrine slows the breakdown of ACh, so it can build up and have a greater effect. However, as Alzheimer’s disease gets worse, there will be less and less ACh, so tacrine may not work as well.
Tacrine may cause liver problems. While taking tacrine, you must have blood tests regularly to see if the medicine is affecting your liver.
Tacrine was available only with your doctor’s prescription. Tacrine (Cognex®) was withdrawn from the US market in May 2012.
Take tacrine only as directed by your doctor. Do not take more or less of it, and do not take it more or less often than your doctor ordered. Taking too much may increase the chance of side effects, while taking too little may not improve your condition.
Tacrine is best taken on an empty stomach (1 hour before or 2 hours after meals). However, if tacrine upsets your stomach, your doctor may want you to take it with food.
Tacrine seems to work best when it is taken at regularly spaced times, usually four times a day.
The dose of tacrine will be different for different patients. Follow your doctor’s orders or the directions on the label. The following information includes only the average doses of tacrine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage form (capsules):
- For treatment of Alzheimer’s disease:
- Adults—To start, 10 milligrams (mg) four times a day. Your doctor may increase your dose gradually if you are doing well on tacrine and your liver tests are normal. However, the dose is usually not more than 40 mg four times a day.
If you miss a dose of tacrine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Along with its needed effects, a medicine may cause some unwanted effects. Some side effects will have signs or symptoms that you can see or feel. Your doctor may watch for others by doing certain tests
Tacrine may cause some serious side effects, including liver problems. You and your doctor should discuss the good tacrine will do as well as the risks of receiving it.
Check with your doctor as soon as possible if any of the following side effects occur:
- Clumsiness or unsteadiness
- loss of appetite
- fast or pounding heartbeat
- high or low blood pressure
- skin rash
- slow heartbeat
- Aggression, irritability, or nervousness
- change in stool color
- convulsions (seizures)
- cough, tightness in chest, troubled breathing, or wheezing
- stiffness of arms or legs, slow movement, or trembling and shaking of hands and fingers
- trouble in urinating
- yellow eyes or skin