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Synalgos-DC

Generic Name: aspirin, caffeine, and dihydrocodeine (AS pir in, KAF een, and dye HYE dro KOE deen)
Brand Name: Synalgos-DC

Medically reviewed by Drugs.com on Apr 18, 2018 – Written by Cerner Multum

What is Synalgos-DC?

Synalgos-DC is a combination medicine used to treat moderate to severe pain.

Synalgos-DC contains dihydrocodeine, an opioid (narcotic) medicine, and may be habit-forming.

Synalgos-DC may also be used for purposes not listed in this medication guide.

Important Information

MISUSE OF OPIOID MEDICINE CAN CAUSE ADDICTION, OVERDOSE, OR DEATH. Keep the medication in a place where others cannot get to it.

Do not give this medicine to anyone younger than 12 years old, or anyone under 18 who recently had surgery to remove the tonsils or adenoids.

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

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 Synalgos-DC if you are allergic to aspirin, caffeine, or dihydrocodeine, or if you have:

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.

Synalgos-DC is not approved for use by anyone 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.

Tell your doctor if you have ever had:

Do not give this medicine to a teenager with a fever, flu symptoms, or chicken pox. Aspirin can cause Reye's syndrome, a serious and sometimes fatal condition in adolescents.

If you use opioid medicine 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 opioids 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. Dihydrocodeine can pass into breast milk and cause drowsiness, breathing problems, or death in a nursing baby.

How should I take Synalgos-DC?

Follow the directions on your prescription label and read all medication guides. Never use this medicine in larger amounts, or for longer than prescribed. Tell your doctor if you feel an increased urge to take more of this medicine.

Never share opioid medicine with another person, especially someone with a history of drug abuse or addiction. MISUSE CAN CAUSE ADDICTION, OVERDOSE, OR DEATH. Keep the medication in a place where others cannot get to it. Selling or giving away opioid medicine is against the law.

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. You should be aware if anyone is using it 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 Synalgos-DC is used for pain, you are not likely to miss a dose. Skip any missed dose if it is almost time for your next dose. Do not use two doses at one time.

What happens if I overdose?

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

Overdose symptoms may include extreme drowsiness, muscle weakness, slow heartbeats, dilated or pinpoint pupils, ringing in your ears, feeling hot, fainting, blue lips, cold and clammy skin, very slow breathing, or coma.

What should I avoid while taking Synalgos-DC?

Avoid driving or operating machinery until you know how Synalgos-DC will affect you. Dizziness or drowsiness can cause falls, accidents, or severe injuries.

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

Ask a doctor or pharmacist before using other medicines for pain, fever, swelling, or cold/flu symptoms. They may contain caffeine or ingredients similar to aspirin (such as ibuprofen, ketoprofen, or naproxen).

Synalgos-DC 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.

Opioid medicine can slow or stop your breathing, and death may occur. 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.

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

Call your doctor at once if you have:

  • noisy breathing, sighing, shallow breathing;

  • a light-headed feeling, like you might pass out;

  • little or no urination;

  • 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 Synalgos-DC?

You may have breathing problems or withdrawal symptoms if you start or stop taking certain other medicines. Tell your doctor if you also use an antibiotic, antifungal medication, heart or blood pressure medication, seizure medication, or medicine to treat HIV or hepatitis C.

Opioid medication 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 affect Synalgos-DC, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here.

Further information

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.

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

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