Quick Answer
In general, no. When practiced by a physician with proper training, acupuncture has a safety profile considered excellent — superior, in many cases, to that of analgesic and anti-inflammatory medications used for the same symptoms. Serious adverse events are rare; mild and transient reactions occur in a minority of patients.
The most common reactions are minor and self-limited: pinpoint bruising at the needle site, mild drowsiness after the session, a feeling of tiredness, and sometimes a brief worsening of the symptom during the first 24-48 hours (the "initial reaction" effect). Serious events — pneumothorax, infection, nerve injury — are rare and technique-dependent: they do not occur with a trained professional following basic protocols.
The Risk Profile of Acupuncture
Large epidemiological studies have mapped the adverse-event profile of acupuncture. Mild events run at a few per thousand sessions; serious events, when they happen, almost always trace back to a failure of technique or hygiene.
Common Mild Effects (and What They Mean)
Mild reactions after acupuncture are part of the therapeutic process and usually clear within 24 to 48 hours. Knowing about them beforehand prevents unnecessary anxiety:
Pinpoint bruising
A small bluish mark (1-3 mm) at the needle site, usually painless. More common in patients with fragile capillaries or those on aspirin or anticoagulants. Clears in a few days.
Post-session drowsiness
A feeling of deep relaxation and an urge to sleep in the following hours. Reflects the parasympathetic activation the technique induces. Avoid long drives if it is intense.
Tiredness
Mild fatigue in the next 24 hours, especially after the first session. Reflects neurovegetative adaptation. Resolves spontaneously.
Initial reaction (transient worsening)
In 5-10% of patients with chronic pain, a brief worsening of the symptom can occur in the first 24-48 hours, followed by improvement. Known as a "healing reaction" or "initial rebound." Not a reason to stop treatment.
Mild dizziness or sweating
Especially in patients who are fasting, anxious, or have low blood pressure. Clears within minutes with proper positioning. Eating beforehand prevents it.
Persistent local sensation
The point may remain tender for a few hours, especially after dry needling at a trigger point. Generally a "worked muscle" sensation, similar to post-exercise soreness.
Serious Adverse Events (Rare)
Serious adverse events in acupuncture almost always trace back to a technical failure — deep needling in the thoracic region without anatomical knowledge, using a non-sterile needle, or treating a patient with an unidentified contraindication. That is why choosing the right professional is the main preventive measure.
Pneumothorax
Accidental lung puncture from inserting a needle too deeply in the posterior thoracic or supraclavicular region. Rare with a trained professional who knows the depth limits in each área. Warning signs: chest pain and worsening shortness of breath after a session.
Local or systemic infection
Practically nonexistent with a sterile disposable needle and proper antisepsis. Signs: progressive redness, warmth, purulent discharge at the needle site. Seek medical care.
Nerve injury
Rare. Usually self-limited local numbness lasting days to weeks. Permanent injuries require a technical error in a high-risk anatomical region.
Vasovagal syncope
Fainting during the session due to a vagal reflex — more common in anxious, fasting, or first-time patients. Prevented with supine positioning and a light meal beforehand.
Extensive bleeding
Large hematomas can occur in anticoagulated patients if the technique is not adjusted. Always tell the physician about any anticoagulant use.
Real Contraindications
There are few absolute contraindications. Most situations call for a technical adjustment, not suspension. The relevant contraindications are:
Severe uncontrolled coagulopathy
Decompensated hemophilia or a very low platelet count (<20,000) rules out needle insertion. Patients on anticoagulants with controlled INR or on aspirin can receive acupuncture with appropriate technique.
Local infection
Do not insert needles in an área with cellulitis, abscess, open wound, or active herpes.
Skin tumor or established lymphedema
Áreas with tumor or chronic lymphedema (especially post-mastectomy) require special care — avoid needling the affected limb.
Nearby metallic prostheses
Do not insert needles over a joint prosthesis. Electroacupuncture is avoided in patients with an implanted pacemaker or defibrillator.
Acute clinical instability
Recent myocardial infarction, acute stroke, sepsis, or severe cardiac decompensation: not the moment to start acupuncture. Once the patient stabilizes, treatment can begin.
Patient refusal
Severe needle phobia that does not respond to desensitization points to alternatives: laser, auriculotherapy with seeds, tuina.
Acupuncture and Medications
There is no pharmacokinetic interaction between acupuncture and medications: the technique is mechanical and neurophysiological, with no substance absorbed. Even só, some technical adjustments may be needed depending on the medication:
Always tell your physician if you are taking:
- 01
Anticoagulants (warfarin, rivaroxaban, dabigatran, apixaban)
- 02
Antiplatelet agents (aspirin, clopidogrel, ticagrelor)
- 03
Immunosuppressants (high-dose corticosteroids, cyclosporine, biologics)
- 04
Insulin and oral antidiabetics
- 05
Antihypertensives with risk of postural hypotension
- 06
Implanted pacemaker or defibrillator (electroacupuncture is avoided)
- 07
Ongoing chemotherapy or radiotherapy
- 08
Antiarrhythmics with risk of bradycardia (electroacupuncture is adjusted)
In all of these cases, acupuncture generally can be performed — only with adjustments to technique, number of points, and modality. The trained medical acupuncturist makes these adaptations as a matter of routine.
How to Reduce the Risk in a Session
Choosing the right professional is the main safety measure. Practical criteria:
Physician with CRM registration and acupuncture training
In Brazil, medical acupuncture is regulated by the Federal Council of Medicine (CFM). Check the physician's CRM and certification in acupuncture, or in physiatry with specific training.
Sterile disposable single-use needle
Individually sealed packaging, opened in front of you. Refuse any technique that reuses needles — even "sterilized" ones.
Complete history before the first session
The physician should always ask about medications, prior conditions, allergies, pregnancy, pacemaker, and prostheses. A rushed history is a warning sign.
Comfort to question the technique
You have the right to know which point is being needled, why, and at what depth. A good physician explains this readily.
Myths and Facts
Myth vs. Fact
Acupuncture "moves toxins" and that is why it causes tiredness.
Post-session drowsiness and tiredness reflect the parasympathetic activation induced by the technique — neurovegetative relaxation. There is no literal "movement of toxins."
Acupuncture can cause paralysis.
Permanent nerve injury is extremely rare and only happens through technical error in a high-risk anatomical region. A trained professional knows the depth limits at every site.
Patients on anticoagulants cannot receive acupuncture.
They can, with technical adjustment: thinner needles, fewer points, reduced depth, post-removal pressure. Always report use and dose.
Acupuncture in the spine can cause spinal cord injury.
Practically impossible with a trained professional who knows cervical and thoracic anatomy. The safe depth is well established and respected.
If acupuncture causes worsening, the physician chose the wrong point.
A transient initial reaction (brief worsening followed by improvement) occurs in 5-10% of patients with chronic pain. It signals neurovegetative adaptation, not technical error.
Frequently Asked Questions
Frequently Asked Questions
Yes. Aspirin slightly raises the chance of pinpoint bruising but is not a contraindication. The physician adjusts the technique and applies pressure after removing the needle.
Manual acupuncture without electrical current is fine. Electroacupuncture is avoided in patients with a pacemaker or defibrillator. Choose a physician who knows about the device.
Practically zero with a single-use disposable needle. Each needle comes in its own sealed pack, is opened at the session, and is dropped into a sharps container afterward. Refuse anything else.
That is why acupuncture is performed by a physician — who evaluates the complaint, orders tests when needed, and spots warning signs. The risk of masking arises when patients receive acupuncture without proper workup.
Yes — and it is strongly indicated for controlling nausea, peripheral neuropathy, and cancer-related fatigue. The technique is adjusted to platelet and neutrophil counts.
Yes. There is no contraindication. Just avoid needling the vaccination arm for 24-48 hours if it is still sore.
Related Reading
Deepen your knowledge with related articles
Safety in Acupuncture: Risks and Contraindications
Detailed guide to precautions and contraindications.
Does Acupuncture Hurt? What You Really Feel
The difference between an acupuncture needle and an injection, and the deqi sensation.
First Acupuncture Session
What to expect before, during, and after.