Decongestants and Blood Pressure Medications: What You Need to Know About the Risks

Many people reach for decongestants when they have a cold or allergies. It’s quick, easy, and available without a prescription. But if you have high blood pressure, that little bottle of Sudafed or a multi-symptom cold tablet could be doing more harm than good. The problem isn’t just about feeling worse-it’s about risking your heart, your arteries, and even your life.

How Decongestants Work-and Why They’re Dangerous for Hypertension

Decongestants like pseudoephedrine and phenylephrine shrink swollen blood vessels in your nose to help you breathe. That’s exactly what they’re designed to do. But here’s the catch: they don’t stop at your nasal passages. These drugs activate alpha-adrenergic receptors all over your body, causing blood vessels to tighten everywhere. That means your heart has to pump harder to push blood through narrower arteries. The result? A spike in blood pressure.

Studies show that even a single dose of pseudoephedrine can raise systolic blood pressure by 2 to 5 mm Hg on average. For most people, that’s not a big deal. But for someone with uncontrolled hypertension, that small increase can be enough to trigger a dangerous event. In rare cases, it’s led to heart attacks, strokes, and irregular heart rhythms. A case published in US Pharmacist described a 5-year-old girl whose blood pressure jumped to 135/80 after just four days of taking phenylephrine. Her numbers returned to normal once she stopped the medication.

Which Decongestants Are the Most Risky?

Not all decongestants are the same. The two most common-and most dangerous-are:

• Pseudoephedrine (found in Sudafed, Claritin-D, Zyrtec-D): This is the most studied and most potent. It’s been linked to measurable increases in blood pressure and heart rate. Because of this, it’s kept behind the pharmacy counter in the U.S. under the Combat Methamphetamine Epidemic Act.
• Phenylephrine (found in Sudafed PE, Mucinex Sinus Max, Tylenol Cold & Flu): Once thought to be safer, newer research shows it can still raise blood pressure, especially in sensitive individuals. It’s now the most common decongestant in OTC products, making it harder to avoid.

Other decongestants like ephedrine, naphazoline, and oxymetazoline (in nasal sprays like Afrin) carry similar risks. Even topical sprays can get absorbed into your bloodstream, especially if used for more than a few days.

Why Multi-Symptom Products Are a Hidden Trap

Most people don’t realize they’re taking a decongestant because it’s hidden inside a cold and flu combo pill. Look at the label of these popular products:

• Tylenol Cold and Flu
• Advil Multi-Symptom Cold and Flu
• Benadryl Allergy Plus Congestion
• Mucinex Sinus Max
• DayQuil and NyQuil (some versions)

All of these contain pseudoephedrine or phenylephrine. If you’re taking one of these for a stuffy nose, you’re also getting a cardiovascular punch. Many patients report spikes in blood pressure after taking these “just for a few days.” The American Society of Health-System Pharmacists found that about 15% of people with high blood pressure still use these products-often because they didn’t realize the decongestant was in there.

Who’s at Highest Risk?

Not everyone with high blood pressure will react the same way. But certain groups are far more vulnerable:

• Those with uncontrolled hypertension (blood pressure consistently above 140/90)
• People with heart disease, heart failure, or arrhythmias
• Patients with Prinzmetal angina (a rare type of chest pain caused by artery spasms)
• Those taking MAO inhibitors (like Nardil or Parnate) or tricyclic antidepressants

Even if your blood pressure is controlled with medication, decongestants can interfere with how well your drugs work. Beta-blockers, ACE inhibitors, and diuretics may not be able to keep up with the sudden increase in vascular resistance caused by a decongestant.

What About Sodium in Cold Medicines?

Another hidden danger? Sodium. Many liquid cold medicines, especially syrups and effervescent tablets, contain high levels of sodium as a preservative or flavoring agent. For someone on a low-sodium diet to manage hypertension, this can be just as harmful as the decongestant itself. A single dose of some liquid cold remedies can contain more than 200 mg of sodium-nearly 10% of the daily recommended limit.

Safe Alternatives for Nasal Congestion

You don’t have to suffer through a stuffy nose just because you have high blood pressure. There are safer options:

• Saline nasal sprays or rinses (like Neti pots): These physically flush out mucus without affecting your blood pressure.
• Steam inhalation: Breathing in warm, moist air from a bowl or shower helps loosen congestion naturally.
• Antihistamines without decongestants: Like loratadine (Claritin) or cetirizine (Zyrtec)-but only if your congestion is allergy-related, not from a cold.
• Humidifiers: Keeping the air moist reduces nasal dryness and swelling.

Even these alternatives should be discussed with your doctor, especially if you’re on other medications. Some antihistamines can cause drowsiness or interact with blood pressure drugs.

What Should You Do Before Taking Anything?

Here’s a simple rule: Never take an OTC cold medicine without checking the label for decongestants and sodium. Look for these words:

• Pseudoephedrine
• Phenylephrine
• Ephedrine
• Naphazoline
• Oxymetazoline
• Sodium (in the ingredients list)

If you’re unsure, ask your pharmacist. They’re trained to spot these risks. In fact, pharmacists in the U.S. now spend an average of 3 to 5 minutes per transaction counseling patients on decongestant risks-especially during cold and flu season.

The American Heart Association’s message is clear: “Just because it’s available without a prescription doesn’t mean it’s safe for everyone.”

When to Call Your Doctor

If you’ve taken a decongestant and notice any of these symptoms, stop the medication and contact your doctor right away:

• Severe headache
• Chest pain or pressure
• Fast, pounding, or irregular heartbeat
• Shortness of breath
• Sudden dizziness or vision changes

These could be signs of dangerously high blood pressure or a cardiac event. Don’t wait. Even if you feel fine, if you’re unsure whether a medication is safe, get it checked.

Final Takeaway: Know What’s in Your Medicine

High blood pressure affects nearly one in three adults in the U.S. Many of them take OTC cold remedies without realizing the risks. The truth is, decongestants aren’t off-limits for everyone with hypertension-but they’re not harmless either. For those with controlled blood pressure, occasional use under medical supervision might be okay. For others, even a single dose can be risky.

Your best defense? Read every label. Ask your pharmacist. Choose non-medicated options when you can. And remember: if it’s meant to shrink blood vessels in your nose, it’s also shrinking them in your heart and brain. That’s not worth the risk.