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Generic name: tacrine (TAK-reen)
Brand name: Cognex

Cognex is used for:

Treating mild to moderate dementia (eg, impairment of memory or judgement, abstract thinking, changes in personality) in patients with Alzheimer disease.

Cognex is a cholinesterase inhibitor. It works by increasing the amount of a certain substance (acetylcholine) in the brain. This may help reduce symptoms of dementia in patients with Alzheimer disease.

Do NOT use Cognex if:

  • you are allergic to any ingredient in Cognex
  • you have too much bilirubin in your blood
  • you have symptoms of an allergic reactions (eg, rash fever) along with abnormal liver function tests
  • you have previously taken Cognex and developed yellowing of the skin or eyes

Contact your doctor or health care provider right away if any of these apply to you.

Before using Cognex:

Some medical conditions may interact with Cognex. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have a history of liver problems, abnormal liver function tests, certain heart problems (eg, slow or irregular heartbeat, sick sinus syndrome), low blood pressure, stomach or bowel problems (eg, ulcer, blockage), lung or breathing problems (eg, asthma, chronic obstructive pulmonary disease [COPD]), urinary blockage, metabolism problems, or Parkinson disease
  • if you have brain lesions or tumors, increased pressure in the brain, a history of seizures (eg, epilepsy), or you have had a recent head injury
  • if you have dementia or other decreased mental ability that is not caused by Alzheimer disease
  • if you are scheduled to have surgery or other medical procedures with general anesthesia

Some MEDICINES MAY INTERACT with Cognex. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Nonsteroidal anti-inflammatory drugs (NSAIDs) (eg, ibuprofen) because the risk of stomach or bowel bleeding may be increased
  • Cholinergic agents (eg, bethanechol), cholinesterase inhibitors (eg, donepezil), or fluvoxamine because they may increase the risk of Cognex's side effects
  • Theophylline because the risk of its side effects may be increased by Cognex
  • Anticholinergics (eg, scopolamine) because their effectiveness may be decreased by Cognex

This may not be a complete list of all interactions that may occur. Ask your health care provider if Cognex may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use Cognex:

Use Cognex as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Take Cognex by mouth between meals, unless your doctor tells you otherwise. If stomach upset occurs, take with food to reduce stomach irritation.
  • Take Cognex on a regular schedule to get the most benefit from it.
  • Taking Cognex at the same time each day will help you remember to take it.
  • Continue to take Cognex even if you feel well. Do not miss any doses.
  • If you miss a dose of Cognex, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once. Contact your doctor if you miss several doses of Cognex. Your doctor may need to restart your medicine at a lower dose to avoid side effects.

Ask your health care provider any questions you may have about how to use Cognex.

Important safety information:

  • Cognex may cause dizziness, drowsiness, or fainting. These effects may be worse if you take it with alcohol or certain medicines. Use Cognex with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
  • Do NOT take more than the recommended dose without checking with your doctor.
  • Do not decrease the dose of Cognex or suddenly stop taking it without checking with your doctor. Decreased mental function and behavior disturbances may occur.
  • When you begin taking Cognex, your doctor will increase your dose slowly over several months. This may help to decrease the risk of certain side effects (eg, nausea, vomiting, diarrhea). Carefully follow the dosing schedule prescribed by your doctor.
  • Tell your doctor or dentist that you take Cognex before you receive any medical or dental care, emergency care, or surgery.
  • Lab tests, including liver function, may be performed while you use Cognex. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
  • Cognex should not be used in CHILDREN; safety and effectiveness in children have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Cognex while you are pregnant. It is not known if this medicine is found in breast milk. Cognex is not approved for use in women who may be breast-feeding.

Possible side effects of Cognex:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Constipation; diarrhea; gas; loss of appetite; muscle aches or pain; nausea; stomach upset; stuffy nose; vomiting; weight loss.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); bloody or black, tarry stools; chest pain; dark urine; decreased coordination; decreased urination; fainting; fever; new or worsening mental or mood problems; pale stools; seizures; severe or persistent dizziness or headache; severe or persistent stomach pain; slow or irregular heartbeat; swelling of the hands, ankles, or feet; tremor; yellowing of the skin or eyes.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include increased sweating or saliva production; muscle weakness; seizures; severe dizziness; severe nausea or vomiting; slow heartbeat; slow or shallow breathing.

Proper storage of Cognex:

Store Cognex between 68 and 77 degrees F (20 and 25 degrees C). Brief storage at temperatures between 59 and 86 degrees F (15 and 30 degrees C) is permitted. Store away from heat, moisture, and light. Do not store in the bathroom. Keep Cognex out of the reach of children and away from pets.

General information:

  • If you have any questions about Cognex, please talk with your doctor, pharmacist, or other health care provider.
  • Cognex is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take Cognex or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about Cognex. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Cognex. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using Cognex.

Issue Date: June 3, 2015

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.