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Dynahist ER (Generic Pseudoephedrine)

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Why is this medication prescribed?

Pseudoephedrine is used to treat hay fever, allergies, and cold-related nasal congestion. Moreover, it is employed to momentarily reduce sinus pressure and congestion. Although pseudoephedrine will alleviate symptoms, it won’t address their underlying cause or hasten the healing process. Pseudoephedrine belongs to the group of drugs known as nasal decongestants. It causes the blood vessels in the nasal passages to constrict, which is how it works.

How should this medicine be used?

Pseudoephedrine is available as a conventional tablet, a 12- or 24-hour extended-release tablet (long-acting), and a solution (liquid) that should be ingested. Every 4 to 6 hours, the standard tablets and fluids are typically consumed. The 12-hour extended-release pills are typically given every 12 hours, and a 24-hour period should not contain more than two doses. You should only take one dose of the 24-hour extended-release tablets each day, and you should wait 24 hours between doses. Take the final dose of the day several hours before bed to help prevent insomnia. Pay close attention to the instructions on the package label or the label on your prescription, and ask your doctor or pharmacist to clarify any instructions you do not understand. Follow the pseudoephedrine directions exactly. Never take it in larger or less amounts or more frequently than recommended by your doctor or the label.

Both alone and in combination with other drugs, pseudoephedrine is sold. Find out which product is best for your symptoms by consulting your doctor or pharmacist. When using two or more non-prescription cough and cold medications simultaneously, carefully read the labelling. If you take these products together, you can experience an overdose because they might both contain the same active ingredient. This is crucial if you plan to give children cough and cold drugs.

Products that contain pseudoephedrine, especially those sold without a prescription, can have fatal side effects in young infants. Pseudoephedrine medications sold over the counter should not be given to children under the age of 4. If you provide these goods to kids between the ages of 4 and 11, use caution and pay close attention to the instructions on the container. Children under the age of 12 should not be given extended-release pseudoephedrine pills.

Be sure the product is appropriate for a child of that age by carefully reading the package label before administering a child pseudoephedrine or a combination product that contains it. Products containing pseudoephedrine intended for adults should not be given to children.

Check the package label before giving a child a pseudoephedrine product to determine how much of the drug the youngster should take. Use the dose on the chart that corresponds to the child’s age. If you are unsure about how much medication to give the child, consult their doctor.

Do not measure your dose if you are consuming the drink with a regular spoon. Use a spoon designed specifically for measuring medication, the measuring cup that came with it, or both.

You should stop taking pseudoephedrine and contact your doctor if your symptoms do not improve within 7 days or if you have a fever.

Do not chew, crack, or crush the extended-release pills; instead, swallow them whole.

Other uses for this medicine

Also, when travelling by air or diving undersea, this drug may be taken to minimise ear pain and obstruction brought on by pressure changes. For further information, speak with your physician or pharmacist.

Ask your doctor or pharmacist for more details if you’re interested in using this drug for any other conditions.

What special precautions should I follow?

Before taking pseudoephedrine,

  • If you have an allergy to pseudoephedrine, any other drugs, or any of the inactive substances in the pseudoephedrine product you intend to take, let your doctor and pharmacist know right away. A list of the ingredients can be found on the package label.
  • If you are currently on an MAO inhibitor, such as isocarboxazid (Marplan), phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), or tranylcypromine (Parnate), or if you have stopped taking an MAO inhibitor within the previous two weeks, avoid taking pseudoephedrine.
  • Inform your doctor and pharmacist about all prescription and over-the-counter drugs, vitamins, dietary supplements, and herbal products that you are now taking or intend to use. Include any drugs you are taking for high blood pressure, asthma, colds, or to control your appetite or diet.
  • Inform your doctor if you have or have had had high blood pressure, glaucoma, diabetes, problems urinating (caused by an enlarged prostate gland), thyroid, or heart illness. Glaucoma is a disorder in which increasing pressure in the eye can cause gradual loss of vision. Inform your doctor if you have ever experienced a digestive obstruction or narrowing if you intend to take the 24-hour extended-release pills.
  • Inform your doctor if you are expecting, intend to get pregnant, or are nursing a baby. Call your doctor if you become pregnant while taking pseudoephedrine.
  • You should inform your doctor or dentist that you are taking pseudoephedrine if you are undergoing surgery, including dental surgery.

What special dietary instructions should I follow?

Large levels of caffeine can exacerbate the negative effects of pseudoephedrine in some foods and beverages.

What should I do if I forget a dose?

Typically, this drug is given as needed. If you regularly take pseudoephedrine as prescribed by your doctor, take the missed dose as soon as you remember. If the next dose is soon due, skip the missed one and carry on with your regular dosing plan. To make up for a missing dose, do not take a second one.

What side effects can this medication cause?

Side effects from pseudoephedrine are possible. If any of these symptoms are severe or do not go away, let your doctor know right once:

  • Restlessness
  • Nausea
  • Vomiting
  • Weakness
  • Headache

Certain adverse effects can be very harmful. Call your doctor right away if you have any of the following symptoms:

  • Nervousness
  • Dizziness
  • Inability to sleep
  • Abdominal pain
  • Having trouble breathing
  • Hammering, rapid, or erratic heartbeat

Further adverse reactions to pseudoephedrine are possible. If you have any strange side effects while taking this medicine, contact your doctor right once.

You or your doctor can submit a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting programme online or by phone if you have a serious side event (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication tightly closed in the original container and out of the reach of children. Keep it away from excessive heat and moisture at room temperature (not in the bathroom).

Unused prescriptions must be disposed of carefully to prevent pets, kids, and other people from ingesting them. You should not, however, dispose of this medication in the toilet. Instead, utilising a medicine take-back programme is the easiest approach to get rid of your medication. To find out about take-back programmes in your area, speak with your pharmacist or the garbage/recycling department in your city. If you do not have access to a take-back programme, see the FDA’s Safe Disposal of Medications website at for additional information.

Although many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and are simple for young children to open, it is crucial to keep all medications out of sight and out of reach of children. Always lock safety caps and promptly stash medication up and away from young children where it is out of their sight and reach to prevent poisoning.

In case of emergency/overdose

Call the poison control hotline at 1-800-222-1222 in the event of an overdose. Moreover, information can be found online at Call 911 right once if the person has collapsed, experienced a seizure, is having difficulty breathing, or cannot be roused.

What other information should I know?

If you are using the 24-hour extended-release tablets, you might see something in your stool that resembles a tablet. The fact that the tablet is empty does not imply that you did not take the whole prescribed amount of medication.

If you have any inquiries concerning pseudoephedrine, ask your pharmacist.

You should keep a written record of every medication you take, including any over-the-counter (OTC) items, prescription drugs, and dietary supplements like vitamins and minerals. This list should be brought with you whenever you see a doctor or are admitted to the hospital. You should always have this information with you in case of emergencies.

Brand names

  • Afrinol®
  • Cenafed®
  • Children’s Sudafed Nasal Decongestant®
  • Congestaclear®
  • Efidac®
  • Myfedrine®
  • Pseudocot®
  • Ridafed®
  • Silfedrine®
  • Sudafed 12/24 Hour®
  • Sudafed Congestion®
  • Sudodrin®
  • SudoGest®
  • Sudrine®
  • Superfed®
  • Suphedrin®
  • Allegra-D® (as a combination product containing Fexofenadine, Pseudoephedrine)
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