What is Theraflu ExpressMax Severe Cold & Flu?

Theraflu ExpressMax is a popular over-the-counter (OTC) cold and flu medicine that provides temporary relief for common symptoms including:

  • Body aches and pains

  • Fever

  • Headache

  • Sore throat

  • Cough

  • Sinus congestion or stuffy nose

  • Runny nose

This product comes in the form of a syrup and contains four active ingredients that each work to target a specific symptom.

Side Effects

The most common side effects from Theraflu ExpressMax include:

  • Drowsiness or trouble sleeping

  • Dizziness

  • Headache

  • Nausea or vomiting

Some uncommon, but more serious side effects include:

  • Confusion

  • Hallucinations

  • Mental or mood changes

  • Shaking

  • Weakness

  • Difficulty urinating

Call 9-1-1 or seek immediate medical attention if you experience chest pain or fast (or irregular) heartbeat after taking this medicine.


Liver Warning: This product contains acetaminophen.

  • Severe liver damage may occur if you take more than 4,000 mg of acetaminophen in a 24 hour period.

  • It is very important to watch out for other sources of acetaminophen and to make sure additive sources of acetaminophen do not go over 4,000 mg a day.

  • Avoid consuming three or more alcoholic beverages every day while using this product.

Allergy Warning: While rare, acetaminophen may cause severe skin reactions in some individuals. Symptoms of this allergy include:

  • Skin reddening

  • Blisters

  • Rash

Stop use and seek medical help immediately if you notice a skin reaction after using this product.

Avoid this product if you are:

  • Under 12 years of age

  • Allergic to acetaminophen

  • Using other prescription or OTC medicines that contain acetaminophen [If you are not sure whether a drug contains acetaminophen, check with your local pharmacist].

  • Taking a monoamine oxidase inhibitor (MAOI) or have taken a MAOI in the past two weeks. If you were on a MAOI before, make sure to wait at least two weeks before using this product. MAOIs are a group of prescription drugs used to treat depression, psychiatric or emotional conditions, or Parkinson's disease. When some ingredients in this product are taken with a MAOI, very serious side effects may occur. If you are unsure if your prescription contains a MAOI, make sure to speak to your doctor or pharmacist before taking this medicine.

Please speak with your doctor prior to using Theraflu ExpressMax if you have:

  • Liver disease

  • Heart disease

  • High blood pressure

  • Thyroid disease

  • Diabetes

  • Trouble urinating due to an enlarged prostate gland

  • Persistent or chronic cough that occurs with smoking / asthma / chronic bronchitis / emphysema / other long-term breathing problems, or a cough that presents with too much phlegm (mucus).

Ask your doctor or pharmacist before use if you are:

  • Taking a blood thinning drug called warfarin

You should stop using Theraflu ExpressMax and seek medical advice from a health care professional if you experience:

  • Nervousness, dizziness, or sleeplessness

  • Pain, nasal congestion, chest congestion, or cough that is worsening or lasts over seven days

  • Fever that exceeds 100 degrees or lasts for more than 3 days

  • Redness or swelling

  • New or worsening symptoms

  • Cough that returns or presents with a rash or headache that does not go away

If you're pregnant or breast-feeding, ask a health professional before using this product.

Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center (1-800-222-1222) right away.


As mentioned above, it's important to avoid using this medicine with MAOIs and other products that contain acetaminophen. It is important to note that most combination cold medicine products and several OTC pain preparations do contain acetaminophen. If you are taking other medications and are unsure if it's ingredients, check with your doctor or pharmacist prior to using this product.


Each serving (30 mL) of Theraflu ExpressMax Severe Cold & Flu cough syrup contains:

  • 650 mg of acetaminophen, a pain reliever and fever reducer

  • 20 mg of dextromethorphan, a cough suppressant

  • 400 mg of guaifenesin, an expectorant

  • 10 mg of phenylephrine, a nasal decongestant


Cabinet Daytime Severe Cold & Flu is a great alternative to Theraflu Expressmax. In fact, medicines from Cabinet Health are:

Curated by Experts: Physicians and pharmacists worked together to provide you with common products you may need. These products are among the best of what’s out there.

Rigorously Tested: All of our factories are FDA-audited, ensuring world-class manufacturing processes and healthy sourcing. After leaving our factories, your medicine goes straight to a Valisure laboratory where each batch is tested for purity, safety (safe from carcinogens and impurities), and gluten (medicines are gluten-free). Believe it or not, this is not a common practice in healthcare!

Better for the Environment: Cabinet has developed the first, and only, non-plastic packaging in pharmaceuticals to address the 194 billion single-use plastic bottles produced by the industry each year. In addition to sustainability in packaging, we invest in plastic offsetting for any plastic still produced in our supply chain, while also providing carbon neutral shipping for all of our customers.


Is it safe to take Theraflu ExpressMax?

This combination cold syrup, when taken as directed, is generally safe. If you're pregnant, breastfeeding, or have other medical conditions, talk to your doctor before using Theraflu ExpressMax.

What are the side effects of Theraflu ExpressMax?

The most common side effects from Theraflu ExpressMax include:

  • Drowsiness or trouble sleeping

  • Dizziness

  • Headache

  • Nausea or vomiting

How long does it take for Theraflu ExpressMax to work?

You may start to feel some symptom relief within 30 minutes.

How much Theraflu ExpressMax should i take?

Adults and children 12 years of age and over may take 30 mL every 4 hours as needed for symptoms. Do not take more than 5 doses (or 150 mL) in 24 hours, unless directed by a doctor.

This product is not recommended for use in children under the age of 12.