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Dihistine DH Liquid

Generic Name: chlorpheniramine/codeine/pseudoephedrine (KLOR-fen-IR-a-meen/KOE-deen/SOO-doe-e-FED-rin)
Brand Name: Phenylhistine DH

Some children have had serious and sometimes fatal breathing problems when using codeine after surgery to remove tonsils or adenoids. Talk with your doctor for more information.

Dihistine DH Liquid is used for:

Treating symptoms of the common cold, flu, or hay fever, and other upper respiratory allergies, such as cough, congestion, runny nose, sneezing, itching of the nose and throat, and itchy, watery eyes. It may also be used for other conditions as determined by your doctor.

Dihistine DH Liquid is a narcotic antitussive (cough suppressant), antihistamine, and decongestant combination. The antitussive works by suppressing the cough center in the brain. The antihistamine works by blocking the action of histamine, which reduces the symptoms of an allergic reaction, such as itchy, watery eyes and runny nose. The decongestant shrinks swollen nasal passages, which relieves nasal congestion.

Do NOT use Dihistine DH Liquid if:

  • you are allergic to any ingredient in Dihistine DH Liquid or any other codeine-related medicine (eg, dihydrocodeine)
  • you have severe high blood pressure, severe heart problems, or heart blood vessel problems
  • you have ulcers, narrow-angle glaucoma, trouble urinating, or if you are unable to urinate
  • you are taking sodium oxybate (GHB) or if you have taken furazolidone or a monoamine oxidase inhibitor (MAOI) (eg, phenelzine) within the last 14 days
  • the patient is a child and has just had surgery to remove tonsils or adenoids

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

Before using Dihistine DH Liquid:

Some medical conditions may interact with Dihistine DH Liquid. 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 alcohol or drug abuse, dependence on narcotics, mental or mood problems, or suicidal thoughts or behaviors
  • if you have increased pressure in the head, an unusual growth in the brain (eg, tumor), a recent head injury, Parkinson disease, Reye syndrome, the blood disease porphyria, or a blockage of your stomach, bowel, or bladder
  • if you have a history of epilepsy or seizures, lung or breathing problems (eg, asthma, emphysema, sleep apnea, croup), stomach or bowel problems, ulcers, chronic constipation, liver or kidney problems, glaucoma or increased pressure in the eye, an enlarged prostate gland or other prostate problems, difficulty urinating, heart problems, diabetes, high blood pressure, blood vessel problems, adrenal gland problems, gallbladder problems, an overactive or underactive thyroid, irregular heartbeat, stroke, chronic cough, or if your cough occurs with large amounts of mucus
  • if you have recently had surgery

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

  • Digoxin or droxidopa because the risk of irregular heartbeat or heart attack may be increased
  • Furazolidone, linezolid, or MAOIs (eg, phenelzine ) because severe high blood pressure and fever may occur.
  • Barbiturates (eg, phenobarbital), beta-blockers (eg, propranolol), cimetidine, catechol-O-methyltransferase (COMT) inhibitors (eg, tolcapone), HIV protease inhibitors (eg, ritonavir), sodium oxybate (GHB), urinary alkalinizers (eg, potassium citrate), or tricyclic antidepressants (eg, amitriptyline) because they may increase the risk of Dihistine DH Liquid's side effects, including severe drowsiness and trouble breathing
  • Quinidine or rifampin because they may decrease Dihistine DH Liquid's effectiveness
  • Bromocriptine or hydantoins (eg, phenytoin) because the risk of their side effects may be increased by Dihistine DH Liquid
  • Guanadrel, guanethidine, mecamylamine, methyldopa, mexiletine, or reserpine because their effectiveness may be decreased by Dihistine DH Liquid
  • Naltrexone because it may decrease Dihistine DH Liquid's effectiveness. Withdrawal symptoms may also occur in patients who are physically dependent on opioids. You must not take naltrexone until you have stopped Dihistine DH Liquid for 7 to 10 days and you have had a negative naloxone challenge test

This may not be a complete list of all interactions that may occur. Ask your health care provider if Dihistine DH Liquid 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 Dihistine DH Liquid:

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

  • Take Dihistine DH Liquid by mouth with or without food. If stomach upset occurs, take with food to reduce stomach irritation.
  • Use a measuring device marked for medicine dosing. Ask your pharmacist for help if you are unsure of how to measure your dose.
  • If you miss a dose of Dihistine DH Liquid and you are taking it regularly, 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.

Ask your health care provider any questions you may have about how to use Dihistine DH Liquid.

Important safety information:

  • Dihistine DH Liquid may cause dizziness, drowsiness, or blurred vision. These effects may be worse if you take it with alcohol or certain medicines. Use Dihistine DH Liquid with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
  • Do not drink alcohol or use medicines that may cause drowsiness (eg, sleep aids, muscle relaxers) while you are using Dihistine DH Liquid; it may add to their effects. Ask your pharmacist if you have questions about which medicines may cause drowsiness.
  • Do NOT take more than the recommended dose or use for longer than prescribed without checking with your doctor.
  • If your symptoms do not get better within 7 days, or if you develop a high fever or persistent headache, check with your doctor.
  • Tell your doctor or dentist that you take Dihistine DH Liquid before you receive any medical or dental care, emergency care, or surgery.
  • Use Dihistine DH Liquid with caution in the ELDERLY because they may be more sensitive to its effects, especially possible breathing problems and drowsiness.
  • Use Dihistine DH Liquid with extreme caution in CHILDREN younger than 6 years old; safety and effectiveness in these children have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: Do not use Dihistine DH Liquid is you are pregnant. If you think you may be pregnant, contact your doctor right away. Dihistine DH Liquid is found in breast milk. Do not breast-feed while taking Dihistine DH Liquid.

When used for long periods of time or at high doses, Dihistine DH Liquid may not work as well and may require higher doses to obtain the same effect as when originally taken. This is known as TOLERANCE. Talk with your doctor if Dihistine DH Liquid stops working well. Do not take more than prescribed.

When used for longer than a few weeks or at high doses, some people develop a need to continue taking Dihistine DH Liquid. This is known as DEPENDENCE or addiction. An early sign of addiction is medicine ineffectiveness. Dependence is not an issue in terminal illness, when pain relief is more important. If using Dihistine DH Liquid for an extended period of time, do not suddenly stop taking Dihistine DH Liquid without your doctor's approval. If you suddenly stop taking Dihistine DH Liquid, you may have WITHDRAWAL symptoms, including anxiety; diarrhea; fever, runny nose, or sneezing; goose bumps and abnormal skin sensations; nausea; vomiting; pain; rigid muscles; rapid heartbeat; seeing, hearing, or feeling things that are not there; shivering or tremors; sweating; trouble sleeping. Contact your doctor if you notice any of these symptoms after stopping Dihistine DH Liquid.

Possible side effects of Dihistine DH Liquid:

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; dizziness; drowsiness; dry mouth, throat, or nose; excitement; nausea; stomach upset; thickening or mucus in nose or throat; vomiting.

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); confusion; difficulty urinating; fainting; fast, slow, or irregular heartbeat; flushing or redness of face; severe drowsiness; trouble breathing; vision changes.

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 agitation; coma; confusion; deep sleep or loss of consciousness; difficulty breathing; diminished mental alertness; hallucinations; hot or cold skin; large and unchanging pupils; sedation; seizures; shaking; sleeplessness; slow heartbeat; slowed breathing.

Proper storage of Dihistine DH Liquid:

Store Dihistine DH Liquid at room temperature, between 68 and 77 degrees F (20 and 25 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep Dihistine DH Liquid out of the reach of children and away from pets.

General information:

  • If you have any questions about Dihistine DH Liquid, please talk with your doctor, pharmacist, or other health care provider.
  • Dihistine DH Liquid 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 Dihistine DH Liquid 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 Dihistine DH Liquid. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Dihistine DH Liquid. 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 Dihistine DH Liquid.

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.