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Generic Name: acetaminophen, caffeine, and dihydrocodeine (a SEET a MIN oh fen, KAF een, dye HYE droe KOE deen)
Brand Name: Trezix

What is Trezix?

Acetaminophen is a pain reliever that increases the effects of dihydrocodeine.

Caffeine is a central nervous system stimulant. It relaxes muscle contractions in blood vessels to improve blood flow.

Dihydrocodeine is an opioid pain medication, sometimes called a narcotic.

Trezix is a combination medicine used to relieve moderate to severe pain.

Trezix may also be used for purposes not listed in this medication guide.

Important Information

You should not use this medicine if you have a stomach condition called paralytic ileus, or severe or uncontrolled asthma. Do not take more than your recommended dose. Acetaminophen overdose can damage your liver or cause death.

Do not use this medicine if you have used an MAO inhibitor in the past 14 days, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, or tranylcypromine.

This medicine is not for use in anyone under 18.

Stop taking this medicine and call your doctor right away if you have skin redness or a rash that spreads and causes blistering and peeling.

Before taking this medicine

You should not use this medicine if you are allergic to acetaminophen (Tylenol) or dihydrocodeine, or if you have:

  • severe or uncontrolled asthma; or

  • a stomach condition called paralytic ileus.

Do not use Trezix if you have taken an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine.

Do not give this medicine to anyone younger than 18 years old.

To make sure this medicine is safe for you, tell your doctor if you have ever had:

If you use dihydrocodeine while you are pregnant, your baby could become dependent on the drug. This can cause life-threatening withdrawal symptoms in the baby after it is born. Babies born dependent on habit-forming medicine may need medical treatment for several weeks.

Do not breast-feed while taking codeine/tramadol. This medicine can pass into breast milk and cause drowsiness, breathing problems, or death in a nursing baby.

How should I take Trezix?

Follow all directions on your prescription label. Never take this medicine in larger amounts, or for longer than prescribed. An overdose can damage your liver or cause death. Tell your doctor if the medicine seems to stop working as well in relieving your pain.

Dihydrocodeine may be habit-forming. Never share this medicine with another person. MISUSE OF NARCOTIC MEDICINE CAN CAUSE ADDICTION, OVERDOSE, OR DEATH, especially in a child or other person using the medicine without a prescription.

If you need surgery or medical tests, tell the doctor ahead of time that you are using this medicine.

Do not stop using this medicine suddenly after long-term use, or you could have unpleasant withdrawal symptoms. Ask your doctor how to safely stop using the medicine.

Store at room temperature away from moisture and heat. Keep track of your medicine. Dihydrocodeine is a drug of abuse and you should be aware if anyone is using your medicine improperly or without a prescription.

Do not keep leftover opioid medication. Just one dose can cause death in someone using this medicine accidentally or improperly. Ask your pharmacist where to locate a drug take-back disposal program. If there is no take-back program, flush the unused medicine down the toilet.

What happens if I miss a dose?

Since this medicine is used for pain, you are not likely to miss a dose. Skip any missed dose if it is almost time for your next scheduled dose. Do not use extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose can be fatal, especially in a child or other person using the medicine without a prescription.

Overdose symptoms may include extreme drowsiness or insomnia, tremors, fast heart rate, pinpoint pupils, severe muscle weakness, vomiting, loss of appetite, stomach pain, dark urine, seizure (convulsions), blue lips, very slow breathing, or coma.

What should I avoid while taking Trezix?

Do not drink alcohol. Dangerous side effects or death could occur.

This medication may impair your thinking or reactions. Avoid driving or operating machinery until you know how Trezix will affect you. Dizziness or severe drowsiness can cause falls or other accidents.

Ask a doctor or pharmacist before using any other cold, allergy, pain, or sleep medication. Acetaminophen (sometimes abbreviated as APAP) is contained in many combination medicines. Taking certain products together can cause you to get too much acetaminophen which can lead to a fatal overdose.

Trezix side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

In rare cases, acetaminophen may cause a severe skin reaction that can be fatal. This could occur even if you have taken acetaminophen in the past and had no reaction. Stop taking this medicine and call your doctor right away if you have skin redness or a rash that spreads and causes blistering and peeling. If you have this type of reaction, you should never again take any medicine that contains acetaminophen.

Like other narcotic medicines, dihydrocodeine can slow your breathing. Death may occur if breathing becomes too weak. A person caring for you should seek emergency medical attention if you have slow breathing with long pauses, blue colored lips, or if you are hard to wake up.

Call your doctor at once if you have:

  • shallow breathing, slow heartbeat;

  • fast or pounding heart rate, feeling light-headed, fainting;

  • confusion, hallucinations, unusual thoughts or behavior;

  • muscle twitching;

  • problems with urination;

  • severe constipation;

  • liver problems--nausea, upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes); or

  • low cortisol levels-- nausea, vomiting, loss of appetite, dizziness, worsening tiredness or weakness.

Seek medical attention right away if you have symptoms of serotonin syndrome, such as: agitation, hallucinations, fever, sweating, shivering, fast heart rate, muscle stiffness, twitching, loss of coordination, nausea, vomiting, or diarrhea.

Serious side effects may be more likely in older adults and those who are overweight, malnourished, or debilitated.

Long-term use of opioid medication may affect fertility (ability to have children) in men or women. It is not known whether opioid effects on fertility are permanent.

Common side effects include:

  • dizziness, drowsiness, tired feeling, headache;

  • nausea, vomiting, stomach pain, constipation;

  • sweating, itching; or

  • skin rash.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Trezix?

This medicine can interact with many other drugs and cause dangerous side effects or death. Be sure your doctor knows if you also use:

This list is not complete. Other drugs may interact with acetaminophen, caffeine, and dihydrocodeine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your pharmacist can provide more information about Trezix.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 7.01.

Date modified: March 06, 2018
Last reviewed: January 15, 2018