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aspirin, caffeine, and dihydrocodeine

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Pronunciation: AS pir in, KAF een, and dye HYE dro KOE deen

Brand: Synalgos-DC

What is the most important information I should know about aspirin, caffeine, and dihydrocodeine?

Dihydrocodeine can slow or stop your breathing, and may be habit-forming. MISUSE OF THIS MEDICINE CAN CAUSE ADDICTION, OVERDOSE, OR DEATH, especially in a child or other person using the medicine without a prescription.

This medicine is not for use in children younger than 12 years old, and is not for use in anyone under 18 who recently had surgery to remove the tonsils or adenoids.

Taking this medicine during pregnancy may cause life-threatening withdrawal symptoms in the newborn.

Fatal side effects can occur if you use this medicine with alcohol, or with other drugs that cause drowsiness or slow your breathing.

What is aspirin, caffeine, and dihydrocodeine?

Aspirin is a salicylate (sa-LIS-il-ate). It works by reducing substances in the body that cause pain, fever, and inflammation. Caffeine is a central nervous system stimulant. It relaxes muscle contractions in blood vessels to improve blood flow. Dihydrocodeine is related to codeine. It is an opioid pain medication. An opioid is sometimes called a narcotic.

Aspirin, caffeine, and dihydrocodeine is a combination medicine used to treat moderate to severe pain.

Aspirin, caffeine, and dihydrocodeine may also be used for purposes not listed in this medication guide.

What should I discuss with my healthcare provider before taking aspirin, caffeine, and dihydrocodeine?

Aspirin may cause stomach or intestinal bleeding, which can be fatal. This can occur without warning while you are taking this medicine.

You should not use this medicine if you are allergic to aspirin, caffeine, or dihydrocodeine, or if you have:

  • severe asthma, asthma with runny nose and nasal polyps, or other breathing problems;
  • a blockage in your stomach or intestines;
  • hemophilia; or
  • an allergy to NSAIDs (nonsteroidal anti-inflammatory drugs).

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.

In some people, codeine (dihydrocodeine) breaks down rapidly in the liver and reaches higher than normal levels in the body. This can cause dangerously slow breathing and may cause death, especially in a child.

This medicine should not be given to a child younger than 12 years old.

Do not give this medicine to anyone younger than 18 years old who recently had surgery to remove the tonsils or adenoids. Do not give this medicine to a teenager with a fever, flu symptoms, or chicken pox.

To make sure aspirin, caffeine, and dihydrocodeine is safe for you, tell your doctor if you have ever had:

  • a bleeding or blood clotting disorder;
  • a stomach disorder, especially an ulcer or bleeding;
  • liver or kidney disease;
  • asthma or other breathing disorder;
  • seizures;
  • a head injury or brain tumor;
  • drug or alcohol addiction; or
  • if you use a sedative like Valium (diazepam, alprazolam, lorazepam, Ativan, Klonopin, Restoril, Tranxene, Versed, Xanax, and others).

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. Taking aspirin during late pregnancy may cause bleeding in the mother or the baby during delivery.

Do not breast-feed while taking aspirin, caffeine, and dihydrocodeine. This medicine can pass into breast milk and cause drowsiness, bleeding, breathing problems, or death in a nursing baby.

How should I take aspirin, caffeine, and dihydrocodeine?

Follow all directions on your prescription label. Dihydrocodeine can slow or stop your breathing. Never use this medicine in larger amounts, or for longer than prescribed. Tell your doctor if the medicine seems to stop working as well in relieving your pain.

Dihydrocodeine may be habit-forming, even at regular doses. Never share this medicine with another person, especially someone with a history of drug abuse or addiction. MISUSE OF NARCOTIC MEDICINE CAN CAUSE ADDICTION, OVERDOSE, OR DEATH, especially in a child or other person using the medicine without a prescription. Selling or giving away aspirin, caffeine, and dihydrocodeine is against the law.

If you need surgery, tell the surgeon ahead of time that you are using this medicine.

Do not stop using this medicine suddenly, or you could have unpleasant withdrawal symptoms. Ask your doctor how to safely stop using aspirin, caffeine, and dihydrocodeine.

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.

What happens if I miss a dose?

Since this medicine is taken when needed, you may not be on a dosing schedule. If you are on a schedule, take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take 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 of dihydrocodeine can be fatal, especially in a child or another person using the medicine without a prescription.

Overdose symptoms may include extreme drowsiness or insomnia, tremors, fast heart rate, pinpoint pupils, ringing in your ears, fainting, weak pulse, seizure (convulsions), blue lips, shallow breathing, or no breathing.

What should I avoid while taking aspirin, caffeine, and dihydrocodeine?

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

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

Ask a doctor or pharmacist before using any cough, cold, allergy, or pain medication. Many combination medicines contain aspirin or caffeine. Taking certain products together can cause you to get too much of a certain drug.

What are the possible side effects of aspirin, caffeine, and dihydrocodeine?

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

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:

  • noisy breathing, sighing, shallow breathing;
  • a slow heart rate or weak pulse;
  • fast or pounding heart rate, muscle twitching;
  • confusion, unusual thoughts or behavior;
  • infertility, missed menstrual periods;
  • impotence, sexual problems, loss of interest in sex;
  • symptoms of stomach bleeding --bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds; 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 may include:

  • dizziness, drowsiness;
  • nausea, vomiting, constipation; or
  • itching, mild 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.

What other drugs will affect aspirin, caffeine, and dihydrocodeine?

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

  • an NSAID (nonsteroidal anti-inflammatory drug) --ibuprofen (Advil, Motrin), ketorolac;
  • medication to prevent blood clots --dalteparin, desirudin, enoxaparin, fondaparinux, tinzaparin, warfarin, Coumadin;
  • other narcotic medications --opioid pain medicine or prescription cough medicine;
  • drugs that make you sleepy or slow your breathing --a sleeping pill, muscle relaxer, sedative, tranquilizer, or antipsychotic medicine; or
  • drugs that affect serotonin levels in your body --medicine for depression, Parkinson's disease, migraine headaches, serious infections, or prevention of nausea and vomiting.

This list is not complete. Other drugs may interact with aspirin, 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 aspirin, caffeine, and dihydrocodeine.


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.

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