Can Massage Cause Blood Clots? The Real Risk

Massage can contribute to blood clots, but the circumstances matter enormously. The primary danger is not that a standard spa massage creates clots from scratch; rather, vigorous pressure on a limb that already harbors a hidden deep vein thrombosis (DVT) can break that clot free and send it to the lungs as a pulmonary embolism. A separate and distinct risk involves neck massage causing arterial tears that lead to stroke. Case reports documenting these events have accumulated over decades, yet a systematic review covering eleven years of published literature found the overall incidence of serious adverse events from massage to be low.

Dislodging a Clot That Is Already There

The scenario that dominates the medical literature on massage-related blood clots is straightforward: a person has an undiagnosed DVT, usually in a leg, and forceful massage frees part or all of that clot. A case report in BMC Pregnancy and Childbirth described a pregnant woman who developed life-threatening pulmonary embolism after leg massage performed over an unrecognized DVT, concluding that leg massage in patients with deep vein thrombosis should be contraindicated because it can dislodge clots and send them to the lungs.¹ A separate case published in the International Journal of Cardiovascular Sciences documented massive pulmonary embolism in a patient whose rapid-onset breathing difficulty began during a leg massage, and the authors attributed it to mechanical dislodgement of a thrombus.²

The mechanism at play is mechanical. When firm, rhythmic pressure is applied over a vein that contains a clot, it can physically push the clot downstream into larger veins and then into the pulmonary arteries. That same paper noted that forceful leg massages may also damage the inner lining of veins through shear stress, which can trigger platelet aggregation and new clot formation on top of the dislodgement risk.² The trouble is that many people with a DVT do not realize they have one. Leg pain, mild swelling, or a sense of heaviness can easily be mistaken for muscle soreness or poor circulation, which is exactly the kind of complaint that sends someone to a massage therapist in the first place.

When Vigorous Massage Triggers a New Clot

Dislodging an existing clot is the most commonly reported mechanism, but massage can also initiate clot formation in someone who did not have one beforehand. A case published in The Physician and Sportsmedicine described a previously healthy 67-year-old man who developed venous thromboembolism after vigorous deep tissue massage, with no other identifiable risk factors. The authors concluded that vigorous massage or equivalent trauma to the legs should be considered a possible risk factor for blood clots, especially in older adults.³

A case in The Permanente Journal reported internal jugular vein thrombosis, a clot in one of the major veins draining the head, following deep tissue massage of the neck area. The authors noted that internal jugular vein thrombosis is typically associated with infections, venous catheter placement, intravenous drug use, or cancer, making the massage-related case unusual.⁴ What these cases share is aggressive, sustained pressure on vascular structures. Light Swedish massage and deep tissue work are not the same animal when it comes to vessel trauma. The deeper and more forceful the technique, the more plausible it becomes that the massage itself damages vessel walls enough to start the clotting cascade.

A review of deep back massage complications also listed venous thromboembolism among reported adverse effects, alongside hematomas and spinal subdural bleeding.⁵ The pattern across these reports is consistent: the word “vigorous” or “deep” appears in virtually every massage-related clot case. Gentle techniques applied to healthy tissue do not carry the same signal in the literature.

Neck Massage and Stroke

The neck presents a different and arguably more alarming risk. Unlike the legs, where the concern is venous clots traveling to the lungs, the neck contains arteries feeding the brain. Forceful manipulation or sustained pressure on the carotid or vertebral arteries can tear the inner lining of these vessels, a condition called arterial dissection. Once the lining tears, blood collects in the vessel wall, and clots form at the injury site. Those clots can then travel into the brain and block blood flow, causing a stroke.

Several case reports spell this out. A report in BMJ Case Reports described a patient who suffered a massive stroke from internal carotid artery dissection after receiving a massage involving neck manipulation. The patient had no other vascular risk factors, and the authors concluded that the massage most likely precipitated the near-fatal event.⁶ A case in World Neurosurgery documented vertebral artery dissection and subsequent acute stroke after neck massage performed on a patient who had a “crick” in the neck, illustrating that the vertebral arteries are vulnerable to dissection from this kind of force.⁷

A more recent case in the Journal of Craniofacial Surgery described an older adult who developed aphasia and right-sided weakness immediately after cervical massage, with imaging confirming carotid artery dissection along with arterial calcification and an elongated styloid process. The stroke was attributed to the combination of the massage-induced vessel injury, existing plaque rupture, and possible reduced blood flow.⁸ That last detail is telling: patients who already have some degree of arterial calcification or structural anatomic variants face higher risk when their neck arteries are subjected to forceful manipulation. The arteries are less elastic and more prone to tearing.

Mechanical neck massage devices carry risk too. A case in the World Journal of Clinical Cases documented carotid artery thrombosis and subsequent intracranial embolism caused by a neck massager.⁹ The takeaway is that force on the neck, whether from human hands or a device, poses a distinct vascular danger that has nothing to do with the venous clot risks in the legs.

Who Faces the Greatest Risk

If you are young, healthy, and getting a moderate-pressure massage on your back or shoulders, the published evidence offers little reason for concern. The risk concentrates in a few identifiable groups and situations.

Existing DVT: The clearest danger. If you have a known or suspected blood clot in your leg, massage of that limb is contraindicated. The problem is that many DVTs are silent, so anyone with recent surgery, prolonged immobility, leg swelling, or unexplained calf pain should be cautious about vigorous leg massage until a clot has been ruled out.
Older adults: The case of the 67-year-old man who developed clots solely from deep tissue massage, with no other risk factors, led the reporting physicians to flag advanced age as a factor worth considering.³ Blood vessels become stiffer and more fragile with age, and arterial calcification makes cervical dissection more likely during neck manipulation.
People with cardiovascular risk factors: Obesity, diabetes, hypertension, and dyslipidemia all increase baseline clot risk. A case involving a 59-year-old woman with all of those conditions documented massive pulmonary embolism following a month-long course of Ayurvedic lower-leg massage for varicose veins.¹⁰
Pregnancy: Pregnancy itself is a hypercoagulable state, meaning blood clots more readily. The case of massage-induced pulmonary embolism during pregnancy reinforces that leg massage during this period carries additional risk if a DVT is present.¹
Varicose veins: Varicose veins indicate venous insufficiency and can harbor slow-moving or stagnant blood, setting the stage for clots. Vigorous massage directly over varicose veins is a repeatedly flagged concern in the case literature.

None of these risk factors mean you can never get a massage. They mean you should inform your therapist, avoid aggressive pressure on the legs and neck, and seek medical evaluation for any unexplained leg pain or swelling before booking a session focused on those areas.

How Rare Are Serious Adverse Events

Context matters. Hundreds of millions of massages are performed worldwide each year, and the documented clot-related cases number in the dozens across all published literature. A systematic review in Evidence-Based Complementary and Alternative Medicine examined adverse events from massage therapy in pain-related conditions over an eleven-year period and identified 40 reports describing 138 adverse events total. The complications included disc herniation, soft tissue trauma, neurological compromise, spinal cord injury, and arterial dissection, among others. The authors stated that massage therapies are “not totally devoid of risks” but that the incidence of such events is low.¹¹

The review also noted that spinal manipulation combined with massage was repeatedly associated with serious adverse events. That distinction is worth flagging: much of the published harm from “massage” involves techniques that overlap with chiropractic manipulation, particularly of the cervical spine. A standard relaxation massage that avoids aggressive neck rotation and deep pressure on the legs carries a substantially lower risk profile than a session that incorporates spinal joint manipulation.

The Paradox of Massage Preventing Clots

Here is where the picture gets genuinely counterintuitive. While massage over an existing clot is dangerous, gentle calf massage after surgery may actually reduce clot risk. A randomized clinical trial of 165 patients who had undergone total knee replacement found that self-performed calf massage was associated with a significantly lower incidence of DVT compared to the control group who did not perform the massage.¹² The logic is that gentle, rhythmic compression of the calf muscles pushes venous blood upward and prevents the stagnation that allows clots to form in the first place. It mimics, in a cruder way, what intermittent pneumatic compression devices do in hospitals.

Research on how massage affects blood flow supports this mechanism. A study in the Journal of Physical Therapy Science measured blood flow velocity in the popliteal vein (behind the knee) before and after friction massage of the area, finding that velocity rose from about 14 cm/s to about 23 cm/s, a substantial increase.¹³ Faster-moving blood is less likely to clot. A study in the Journal of Applied Physiology confirmed that even brief, superficial effleurage strokes produced a significant increase in local perfusion and modified multiple components of cardiovascular regulation.¹⁴

The evidence is not entirely uniform, though. An older study in the International Journal of Sports Medicine found that effleurage massage of the quadriceps did not significantly elevate arterial or venous blood velocity above resting levels, while light muscle contractions did.¹⁵ The discrepancy may come down to technique, pressure, and the specific region being massaged. Deeper techniques and areas closer to major veins appear more likely to boost flow, while light stroking over large muscle groups may not do much hemodynamically.

The practical upshot is that massage is not inherently pro-clot or anti-clot. When applied gently to limbs without existing clots, it can promote venous return and reduce stasis. When applied forcefully over a vessel that already contains a thrombus, it can turn a contained problem into a medical emergency. The dose and the context determine everything.

Foam Rollers and Self-Massage Devices

The same principles apply to foam rolling and self-myofascial release tools, which have become ubiquitous in gyms and physical therapy clinics. An international Delphi study published in the Journal of Clinical Medicine gathered expert consensus on foam rolling contraindications and found that deep vein thrombosis was rated as a caution by an overwhelming majority of panelists, with agreement ranging from about 92% to 97%.¹⁶ In that study, “caution” meant the technique should be used only with careful consideration rather than being absolutely off-limits, while full contraindications (conditions where you should not foam roll at all) were reserved for open wounds and bone fractures.

Percussion massage guns fall into the same territory, though peer-reviewed data on those devices specifically remains thin. The mechanical principle is the same: sustained, repetitive force applied to tissue overlying a blood vessel can dislodge a clot or damage a vessel wall. If you have any reason to suspect a DVT, whether from recent surgery, long-haul travel, or unexplained unilateral leg swelling, using a percussion gun or foam roller on that leg is unwise until the suspicion has been addressed.

Recognizing Trouble Before and After a Massage

Knowing the warning signs of a DVT before you get on the table is the single most useful piece of prevention. The classic presentation is one-sided leg swelling, warmth, redness, and pain that worsens with standing or walking. Not every DVT announces itself this way; some produce only a vague ache or heaviness that mimics a pulled muscle. If you have any of these symptoms along with a recent period of immobility, a long flight, recent surgery, or a personal or family history of blood clots, getting checked before booking a leg-focused massage is a reasonable precaution.

After a massage, the timeline of reported adverse events varies. Some pulmonary embolisms in the case literature occurred within minutes to hours of the massage, consistent with mechanical dislodgement during the session itself.² In one case, a woman who underwent a month-long course of leg massage developed massive PE during that extended treatment period.¹⁰ For neck-related events, stroke symptoms like sudden speech difficulty, one-sided weakness, facial drooping, or severe headache often appeared immediately or within hours of the cervical manipulation.⁸

If you develop sudden shortness of breath, chest pain, rapid heart rate, or coughing up blood in the hours after a leg massage, get to an emergency department. If you develop any stroke symptoms after neck massage, call emergency services immediately. These are not wait-and-see situations.

What Massage Therapists Screen For

Licensed massage therapists are trained to take health histories and identify contraindications before starting a session. In most jurisdictions, intake forms ask about blood clot history, current anticoagulant use, recent surgeries, and cardiovascular conditions. A competent therapist will avoid deep work on the legs of someone with known DVT risk factors and will decline to perform aggressive cervical manipulation if there are vascular concerns.

The challenge is that the highest-risk patients are often the ones who do not know they are at risk. The pregnant woman with an undiagnosed DVT, the retiree with mild leg pain attributed to aging, the desk worker with a hidden clot from weeks of sitting — none of them would flag anything on an intake form. This is why therapists are also taught to watch for physical signs during the session: unusual heat in one calf, visible swelling, or a cord-like texture in the calf that does not feel like a normal muscle knot. These findings should pause or redirect the session, not power through it. If you are the client, mentioning even vague leg symptoms to your therapist is worth doing. They would rather adjust their technique than deal with an emergency on the table.

1
PubMed Central. Leg massage during pregnancy with unrecognized deep vein thrombosis could be life threatening: a case report
2
International Journal of Cardiovascular Sciences. Massive Pulmonary Embolism After Leg Massage: A Case Report
3
PubMed. Venous thromboembolism following vigorous deep tissue massage
4
PubMed Central. A Rare Cause of Internal Jugular Vein Thrombosis: Deep Tissue Massage
5
Frontiers in Nephrology. Case Report: Kidney injury following non-medical massage
6
PubMed Central. A near-fatal consequence of chiropractor massage: massive stroke from carotid arterial dissection and bilateral vertebral arterial oedema
7
PubMed. “Crick” in Neck Followed by Massage Led to Stroke: Uncommon Case of Vertebral Artery Dissection
8
PubMed. Cervical Artery Dissection and Cerebral Infarction Following Cervical Massage
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PubMed Central. Intracranial large artery embolism due to carotid thrombosis caused by a neck massager: A case report
10
International Journal Of Community Medicine And Public Health. An unusual case of pulmonary embolism following ayurveda massage therapy
11
PubMed Central. Adverse events of massage therapy in pain-related conditions: a systematic review
12
PubMed Central. Effect of self-calf massage on the prevention of deep vein thrombosis after total knee arthroplasty: A randomized clinical trial
13
PubMed Central. Effects of friction massage of the popliteal fossa on blood flow velocity of the popliteal vein
14
PubMed. Lower limb massage in humans increases local perfusion and impacts systemic hemodynamics
15
PubMed. Effleurage massage, muscle blood flow and long-term post-exercise strength recovery
16
PubMed Central. Expert Consensus on the Contraindications and Cautions of Foam Rolling—An International Delphi Study