If you’re stuffed up and looking for relief, Sudafed is one medication that could help. Sudafed helps relieve nasal and sinus congestion and pressure due to the common cold, hay fever, or upper respiratory allergies.

Here’s what you need to know to use this drug safely to relieve your congestion.

The main active ingredient in Sudafed is called pseudoephedrine (PSE). It’s a nasal decongestant. PSE relieves congestion by making the blood vessels in your nasal passages narrower. This opens up your nasal passages and allows your sinuses to drain. As a result, your nasal passages are clearer and you breathe more easily.

Most forms of Sudafed only contain pseudoephedrine. But one form, called Sudafed 12 Hour Pressure + Pain, also contains the active drug naproxen sodium. Any additional side effects, interactions, or warnings caused by naproxen sodium are not covered in this article.

Sudafed PE products don’t contain pseudoephedrine. Instead, they contain a different active ingredient called phenylephrine.

All forms of Sudafed are taken by mouth. Sudafed Congestion, Sudafed 12 Hour, Sudafed 24 Hour, and Sudafed 12 Hour Pressure + Pain come as caplets, tablets, or extended-release tablets. Children’s Sudafed comes in liquid form in grape and berry flavors.

Below are dosage instructions for the different kinds of Sudafed. You can also find this information on the medication’s package.

Sudafed Congestion

  • Adults and children 12 years and older: Take two tablets every four to six hours. Do not take more than eight tablets every 24 hours.
  • Children ages 6–11 years: Take one tablet every four to six hours. Do not take more than four tablets every 24 hours.
  • Children younger than 6 years: Do not use this medication for children younger than 6 years.

Sudafed 12 Hour

  • Adults and children 12 years and older. Take one tablet every 12 hours. Do not take more than two tablets every 24 hours. Do not crush or chew the caplets.
  • Children younger than 12 years. Do not use this medication for children younger than 12 years.

Sudafed 24 Hour

  • Adults and children 12 years and older. Take one tablet every 24 hours. Do not take more than one tablet every 24 hours. Do not crush or chew the tablets.
  • Children younger than 12 years. Do not use this medication for children younger than 12 years.

Sudafed 12 Hour Pressure + Pain

  • Adults and children 12 years and older. Take one caplet every 12 hours. Do not take more than two caplets every 24 hours. Do not crush or chew the caplets.
  • Children younger than 12 years. Do not use this medication for children younger than 12 years

Children’s Sudafed

  • Children ages 6–11 years. Give 2 teaspoons every four to six hours. Do not give more than four doses every 24 hours.
  • Children ages 4–5 years. Give 1 teaspoon every four to six hours. Do not give more than four doses every 24 hours.
  • Children younger than 4 years. Do not use this medication for children younger than 4 years.

Like most drugs, Sudafed may cause side effects. Some of these side effects may go away as your body gets used to the medication. If any of these side effects are a problem for you or if they don’t go away, call your doctor.

More common side effects

The more common side effects of Sudafed can include:

  • weakness or dizziness
  • restlessness
  • headache
  • nausea
  • insomnia

Serious side effects

The rare but serious side effects of Sudafed can include:

  • very fast heart rate
  • trouble breathing
  • hallucinations (seeing or hearing things that aren’t there)
  • psychosis (mental changes that cause you to lose touch with reality)
  • heart problems, such as chest pain, increased blood pressure, and irregular heartbeat
  • heart attack or stroke

Sudafed may interact with other medications you’re taking. An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well. Talk to your pharmacist or doctor to see if Sudafed interacts with any medications you’re currently taking.

You should not take the following drugs with Sudafed:

  • dihydroergotamine
  • rasagiline
  • selegiline

Also, before taking Sudafed, be sure to tell your doctor if you take any of the following medications:

  • blood pressure or heart medications
  • asthma medications
  • migraine medications
  • antidepressants
  • over-the-counter herbal remedies, such as St. John’s Wort

There are a few warnings you should keep in mind if you take Sudafed.

Conditions of concern

Sudafed is safe for many people. However, you should avoid it if you have certain health conditions, which may get worse if you take Sudafed. Before using Sudafed, be sure to tell your doctor if you have:

Other warnings

There are concerns of misuse with Sudafed because it can be used to make illegal methamphetamine, a very addictive stimulant. However, Sudafed itself is not addictive.

There are also no warnings against drinking alcohol while taking Sudafed. However, in rare cases, alcohol may increase certain side effects of Sudafed, such as dizziness.

If you’ve taken Sudafed for a week and your symptoms don’t go away or get better, call your doctor. Also call if you have a high fever.

In case of overdose

Symptoms of an overdose of Sudafed can include:

  • fast heart rate
  • dizziness
  • anxiety or restlessness
  • increased blood pressure (likely without symptoms)
  • seizures

If you think you’ve taken too much of this drug, call your doctor or local poison control center. If your symptoms are severe, call 911 or go to the nearest emergency room right away.

In most states, Sudafed is available over the counter (OTC). However, some locations in the United States require a prescription. The states of Oregon and Mississippi, as well as some cities in Missouri and Tennessee, all require a prescription for Sudafed.

The reason for these prescription requirements is that PSE, the main ingredient in Sudafed, is used to make illegal methamphetamine. Also called crystal meth, methamphetamine is a highly addictive drug. These requirements help prevent people from buying Sudafed to make this drug.

Efforts to prevent people from using PSE to make methamphetamine also restrict the sale of Sudafed. A piece of legislation called the Combat Methamphetamine Epidemic Act (CMEA) was passed in 2006. It requires you to present a photo ID to buy products that contain pseudoephedrine. It also limits the amount of these products you can buy.

In addition, it requires pharmacies to sell any products that contain PSE behind the counter. That means you can’t buy Sudafed on the shelf at your local drugstore like other OTC medications. You have to get Sudafed from the pharmacy. You also have to show your photo ID to the pharmacist, who is required to track your purchases of products that contain PSE.

Sudafed is one of many drug options available today for treating nasal congestion and pressure. If you have further questions about using Sudafed, ask your doctor or pharmacist. They can help you choose a medication that can help safely relieve nasal symptoms for you or your child.

If you’d like to buy Sudafed, you’ll find a range of Sudafed products here.

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