Medicines are designed to improve health, but every medication has potential risks and side effects. For some drugs, those risks include blood clots, heart attack, or stroke, particularly in people who already have certain cardiovascular risk factors.
That does not mean these medicines are unsafe for everyone. In many cases, their benefits can outweigh their risks when they are appropriately prescribed and monitored.
The important lesson is to know which medicines carry these warnings—and never stop a prescribed medication suddenly without speaking with the healthcare professional who prescribed it.
1. Certain JAK Inhibitors
One important example is a class of medicines called Janus kinase (JAK) inhibitors.
The FDA requires prominent warnings for certain JAK inhibitors, including tofacitinib, baricitinib, and upadacitinib, concerning serious heart-related events, blood clots, and other risks.
These medicines are used to treat certain inflammatory conditions, including rheumatoid arthritis and, depending on the medication, other conditions such as ulcerative colitis.
The risk may be particularly important for people who:
- Are current or former smokers
- Have cardiovascular risk factors
- Have previously experienced a heart attack
- Have had a stroke
- Have previously had blood clots
If you take one of these medications, don’t assume you should discontinue it. Instead, discuss your individual benefits and risks with your healthcare professional.
2. Some Hormonal Birth-Control Pills
Combined hormonal contraceptives contain estrogen and progestin.
Blood clots are an uncommon but recognized serious risk with these medications, and the FDA also notes rare risks of heart attack and stroke.
Risk varies considerably depending on factors such as age, smoking status, medical history, and the specific contraceptive.
This is why contraceptive choices should be individualized rather than based on a general warning about “the pill.”
3. Certain Anti-Inflammatory Painkillers
Some non-aspirin nonsteroidal anti-inflammatory drugs (NSAIDs) can increase the risk of heart attack and stroke.
Examples include commonly used medicines such as:
- Ibuprofen
- Naproxen
- Diclofenac
- Celecoxib
The FDA warns that cardiovascular risk can occur relatively early during NSAID treatment and may increase with higher doses or longer use.
This doesn’t mean everyone should avoid NSAIDs. It means people with cardiovascular disease or other risk factors should discuss appropriate choices and dosing with a healthcare professional.
4. Some Medicines Can Affect Cardiovascular Risk Indirectly
Not every medication associated with heart-related concerns directly causes a blood clot.
Some medicines can affect:
- Blood pressure
- Heart rate
- Fluid balance
- Cholesterol
- Blood sugar
- Kidney function
These effects can be particularly important in people who already have cardiovascular disease or take multiple medications.
For this reason, tell your healthcare professional and pharmacist about all prescription medicines, over-the-counter products, vitamins, and supplements you use.
Who May Have a Higher Risk?
The risk associated with a particular medicine can be greater in people with certain underlying factors, including:
- Previous heart attack or stroke
- Previous blood clots
- High blood pressure
- High cholesterol
- Diabetes
- Smoking
- Obesity
- Older age
- Cardiovascular disease
- Certain inherited or acquired clotting conditions
Having one of these risk factors doesn’t automatically mean you cannot take a particular medication. Your healthcare professional should weigh the potential benefits against the risks.
Don’t Stop Your Medication on Your Own
A frightening headline about blood clots or heart attacks can make someone want to stop taking their medicine immediately.
That can be dangerous.
Some medications need to be continued to control serious conditions, and suddenly stopping certain drugs can cause the underlying condition to worsen or create other health risks.
If you’re concerned about a medication, contact the prescribing clinician or pharmacist before making changes.
Know the Warning Signs of a Blood Clot
A blood clot can occur in a deep vein, commonly in the leg.
Possible warning signs include:
- Swelling in one leg or arm
- Pain or tenderness
- Warmth
- Redness or discoloration
A clot can sometimes travel to the lungs and cause a pulmonary embolism.
Sudden shortness of breath, chest pain, coughing up blood, rapid breathing, fainting, or severe dizziness requires emergency medical attention.
Know the Warning Signs of a Heart Attack
Possible heart-attack symptoms include:
- Pressure, squeezing, or pain in the chest
- Pain spreading to the arm, back, neck, jaw, or upper abdomen
- Shortness of breath
- Cold sweating
- Nausea
- Lightheadedness
Symptoms can vary, particularly in women and older adults.
If you suspect a heart attack, seek emergency medical care immediately.
What About Aspirin?
Aspirin is sometimes misunderstood because it can reduce the formation of certain blood clots and is prescribed to some people at high cardiovascular risk.
But aspirin is not appropriate for everyone.
It can also cause serious bleeding, including bleeding in the stomach or brain. The FDA advises that daily aspirin therapy should be used under the guidance of a healthcare professional.
Therefore, don’t start taking aspirin simply because you read that it can prevent heart attacks.
How to Use Medicines More Safely
You can reduce medication-related risks by:
- Taking medicines exactly as prescribed
- Reading the medication information provided with your prescription
- Telling every healthcare professional about the medicines you take
- Checking before combining prescription and over-the-counter drugs
- Asking about interactions with supplements and herbal products
- Keeping regular medical appointments
- Reporting new or unusual symptoms promptly
Never assume that an over-the-counter medicine is automatically risk-free.
The Bottom Line
Some medicines really can increase the risk of blood clots, heart attack, or stroke, but the risk depends heavily on the specific medication and the individual taking it.
Certain JAK inhibitors, some estrogen-containing contraceptives, and some NSAID pain relievers are examples of medications with documented cardiovascular warnings.
The answer isn’t to panic—or to stop your medication.
The safest approach is to know your medication’s risks, understand your personal risk factors, and discuss concerns with your healthcare professional.
Medical Disclaimer
This article is for general educational purposes only and does not replace professional medical advice. Medication risks vary according to the specific drug, dose, duration of treatment, medical history, and other medicines being taken. Do not stop, reduce, or change a prescribed medication without consulting the healthcare professional who prescribed it. If you experience symptoms suggestive of a heart attack, stroke, or serious blood clot, seek emergency medical care immediately.