DrugindexOnline^{2nd edition}

Generic name: Tacrine hydrochloride
Brand names: Cognex

Why is Tacrine hydrochloride prescribed?

Cognex is used for the treatment of mild to moderate Alzheimer's disease. This progressive, degenerative disorder causes physical changes in the brain that disrupt the flow of information and affect memory, thinking, and behavior. As someone caring for a person with Alzheimer's, you should be aware that Cognex is not a cure, but has helped some people.

Most important fact about Tacrine hydrochloride

Do not abruptly stop Cognex treatment, or reduce the dosage, without consulting the doctor. A sudden reduction can cause the person you are caring for to become more disturbed and forgetful. Taking more Cognex than the doctor advises can also cause serious problems. Do not change the dosage of Cognex unless instructed by the doctor.

How should you take Tacrine hydrochloride?

This medication will work better if taken at regular intervals, usually 4 times a day. Cognex is best taken between meals; however, if it is irritating to the stomach, the doctor may advise taking it with meals. If Cognex is not taken regularly, as the doctor directs, the condition may get worse.

--If you miss a dose...

Give the forgotten dose as soon as possible. If it is within 2 hours of the next dose, skip the missed dose and go back to the regular schedule. Do not double the doses.

--Storage instructions...

Store at room temperature away from moisture.

What side effects may occur?

Side effects cannot be anticipated. If any develop or change in intensity, tell the doctor as soon as possible. Only the doctor can determine if it is safe to continue giving Cognex.

• More common side effects may include:
  Abdominal pain, abnormal thinking, agitation, anxiety, chest pain, clumsiness or unsteadiness, confusion, constipation, coughing, depression, diarrhea, dizziness, fatigue, flushing, frequent urination, gas, headache, inflamed nasal passages, insomnia, indigestion, liver function disorders, loss of appetite, muscle pain, nausea, rash, sleepiness, upper respiratory infection, urinary tract infection, vomiting, weight loss

Be sure to report any symptoms that develop while on Cognex therapy. You should alert the doctor if the person you are caring for develops nausea, vomiting, loose stools, or diarrhea at the start of therapy or when the dosage is increased. Later in therapy, be on the lookout for rash or fever, yellowing of the eyes and skin, or changes in the color of the stool.

Why should Tacrine hydrochloride not be prescribed?

People who are sensitive to or have ever had an allergic reaction to Cognex (including symptoms such as rash or fever) should not take Tacrine hydrochloride. Before starting treatment with Cognex, it is important to discuss any medical problems with the doctor. If during previous Cognex therapy the person you are caring for developed jaundice (yellow skin and eyes), which signals that something is wrong with the liver, Cognex should not be used again.

Special warnings about Tacrine hydrochloride

Use Cognex with caution if the person you are caring for has a history of liver disease, certain heart disorders, stomach ulcers, or asthma.

Because of the risk of liver problems when taking Cognex, the doctor will schedule blood tests to monitor liver function every other week from at least the fourth week to the sixteenth week of treatment. After 16 weeks, blood tests will be given monthly for 2 months and every 3 months after that. If the person you are caring for develops any liver problems, the doctor may temporarily discontinue Cognex treatment until further testing shows that the liver has returned to normal. If the doctor resumes Cognex treatment, regular blood tests will be conducted again.

Before having any surgery, including dental surgery, tell the doctor that the person is being treated with Cognex.

Cognex can cause seizures, and may cause difficulty urinating.

Possible food and drug interactions when taking Tacrine hydrochloride

If Cognex is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important that you check with your doctor before combining Cognex with the following:

Antispasmodic drugs such as Bentyl and Levsin
Bethanechol chloride (Urecholine)
Cimetidine (Tagamet)
Fluvoxamine
Muscle stimulants such as Mestinon, Mytelase, and Prostigmin
Nonsteroidal anti-inflammatory drugs such as Aleve, Motrin, and Naprosyn
The Parkinson's medications Artane and Cogentin
Theophylline (Theo-24, Uniphyl)

Special information if you are pregnant or breastfeeding

The effects of Cognex during pregnancy have not been studied; and it is not known whether Cognex appears in breast milk.

Recommended dosage

ADULTS

The usual starting dose is 10 milligrams 4 times a day, for at least 4 weeks. Do not increase the dose during this 4-week period unless directed by your doctor.

Depending on the patient's tolerance of the drug, dosage may then be increased at 4-week intervals, first to 20 milligrams, then to 30, and finally to 40, always taken 4 times a day.

CHILDREN

The safety and effectiveness of Cognex have not been established in children.

Overdosage

Any medication taken in excess can have serious consequences. If you suspect an overdose, seek medical attention immediately.

• Symptoms of Cognex overdose include:
  Collapse, convulsions, extreme muscle weakness, possibly ending in death (if breathing muscles are affected), low blood pressure, nausea, salivation, slowed heart rate, sweating, vomiting