Trigger Point Injections: How They Work, What to Expect, and How Long Relief Lasts
Updated: 6 days ago
Written and medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026 · How we review
Quick Answer: What is a trigger point injection?
A trigger point injection is an in-office treatment for myofascial pain in which a provider places a thin needle into a painful muscle knot, called a trigger point, and injects a numbing medicine, sometimes with a steroid or botulinum toxin. It is generally safe, relief usually begins within 24 to 72 hours, and it lasts about a month. [1]
What the research says
Numbing injections eased neck and shoulder knot pain more than dry needling in the short term. A review of 15 randomized trials (884 adults) found pain scores improved by about 1.6 points on a 0–10 scale at 1–4 weeks with local anesthetic injections compared with dry needling, and by about 0.8 points compared with placebo at 2–8 weeks; the evidence was low quality, and the gap versus dry needling was not significant when only double-blinded trials were counted. (Nouged et al., J Oral Facial Pain Headache, 2019) [4]
For neck trigger points, injections beat dry needling for short-term pain, but not for disability. A meta-analysis of 6 trials found pain intensity was 2.13 points lower on average after trigger point injection than after dry needling, with a large effect size, while neck disability, pressure-pain thresholds, neck mobility and mood did not differ. (Navarro-Santana et al., Pain Med, 2022) [5]
Local anesthetic outperformed botulinum toxin, and repeat sessions helped more than one. A review of 33 studies found local anesthetic injections reduced myofascial pain intensity more than botulinum toxin A injections, and multiple sessions of local anesthetic were more beneficial than a single session. (Ahmed et al., Clin J Pain, 2019) [6]
Key takeaways
A trigger point injection targets a painful "knot" in a muscle that has not improved with simpler treatments such as pain relievers, heat, massage, or physical therapy. [1]
The injection usually contains a local anesthetic, with or without a corticosteroid or botulinum toxin; needling without any medicine is called dry needling. [1]
Relief typically starts within 24–72 hours and lasts about a month, and more injections may be advised if pain returns. [1]
It works best alongside physical therapy and stretching, because easing the pain can make those exercises possible. [1]
Serious complications are rare; call your provider for fever or warmth at the injection site. [1]
What are trigger points?
Trigger points are painful knots in a muscle that are very sensitive to touch or pressure. [1] They can form after a sudden injury or from small, repeated strain on the muscle fibers, which leaves those fibers stuck in a contracted state. [1]
You can sometimes feel a trigger point when you rub the muscle. It feels like a small bump, nodule, or knot. [1]
Trigger points are the usual source of the pain and tenderness in myofascial pain syndrome. "Myo" means muscle, and "fascial" refers to the fascia, the thin white connective tissue wrapped around every muscle. [1]
Myofascial pain and trigger points are very common, occurring in about 85% of people at some point in their lives. [1]
What conditions can a trigger point injection treat?
A trigger point injection treats myofascial pain, especially in the neck, shoulders, arms, legs, and lower back. [1] Trigger points can develop in any muscle, but some muscle groups are treated far more often than others. [1]
Muscle | Where it is | Linked problem |
Masseter | Jaw | — |
Temporalis | Side of the head | — |
Sternocleidomastoid | Front of the neck | — |
Levator scapulae | Side of the neck | — |
Trapezius | Back of the neck and shoulders | May cause tension headaches |
Quadratus lumborum | Deep in the low back | — |
Gluteus medius | Hip | — |
Piriformis | Buttock | Piriformis syndrome: buttock pain or numbness down the back of the leg |
Muscles and linked problems from [1].
A trigger point in the trapezius may cause tension headaches. [1] A trigger point in the piriformis, a muscle in the buttock, can press on the sciatic nerve and cause pain or numbness in the buttock and down the back of the leg. [1] You can read more about these muscles in our guides to the sternocleidomastoid muscle, the neck muscles, and the back muscles.
Who is a good candidate for a trigger point injection?
A trigger point injection may be right for you if trigger point pain has not improved with other treatments. [1] These include over-the-counter pain medicine, heat therapy, massage therapy, myofascial release, and physical therapy. [1]
Providers usually pair the injection with physical therapy and stretching. [1] This approach helps most when pain is too intense to stretch or exercise. The injection eases the pain first, so physical therapy can then work better. [1]
Before recommending an injection, your provider will do a thorough physical exam and rule out other causes of your pain, such as: [1]
Structural causes of pain
Spine problems that cause back pain, such as degenerative arthritis, a herniated disk, or spinal stenosis
Radiculopathy, or pain from a pinched nerve
What medicines are used in a trigger point injection?
A trigger point injection most often uses a local anesthetic, either alone or combined with a corticosteroid or botulinum toxin. [1] Some providers needle the knot without injecting any medicine at all. [1]
Option | What it is | Learn more |
Local anesthetic | A numbing medicine, used in most trigger point injections | — |
Local anesthetic + corticosteroid | Numbing medicine combined with a steroid | |
Local anesthetic + botulinum toxin | Numbing medicine combined with botulinum toxin | |
Dry needling | Needling the knot with no medicine injected |
Injections can be done with or without imaging guidance such as ultrasound or fluoroscopy. [2]
What happens during a trigger point injection?
A trigger point injection is done in your provider's office, and you go home the same day. [1] You do not need to do anything special to prepare, but you should tell your provider about your current medicines, symptoms, and overall health. [1]
Here is what usually happens, step by step: [1]
Positioning. You sit or lie on an exam table, depending on where the trigger point is.
Cleaning. Your provider cleans the skin over the area with an alcohol pad.
Marking. Your provider may mark the trigger point with a skin marker.
Holding the knot. After finding the trigger point by touch, your provider pinches it between their fingers to keep the tissue steady. This may feel uncomfortable.
Needling. A thin needle attached to a syringe goes into the trigger point. Your provider moves it in and out in a steady rhythm without fully withdrawing it from the muscle or skin.
Twitching. You will likely feel the muscle twitch or spasm. Your provider keeps needling in several directions until the twitching stops or the muscle feels relaxed.
Injecting. Your provider injects the local anesthetic, with or without a corticosteroid or botulinum toxin.
Going home. The procedure is over, and you can leave.
Does a trigger point injection hurt?
A trigger point injection usually causes some short-lived pain. [1] Because trigger points are tender, you will likely feel pain while your provider finds the knot by touch. [1]
You may feel stinging and burning as the needle and medicine go in. [1] When the needle tip touches the trigger point, your pain may briefly increase. That brief spike is a good sign: it means the needle is in the right spot. [1]
What is recovery like after a trigger point injection?
Recovery after a trigger point injection is quick: you can go home and use the treated muscle right away. [1] Avoid strenuous activity for the first few days. [1]
Temporary discomfort or numbness around the injection site is the most common side effect. [1] Your provider may suggest acetaminophen or ibuprofen for this, and ice packs on the injection site can lower the chance of bruising. [1]
How long does a trigger point injection last?
A trigger point injection typically relieves pain for about a month. [1] Most people notice relief starting 24 to 72 hours after the procedure. [1]
Milestone | What to expect |
Right after the injection | Possible soreness or numbness at the site |
First few days | Use the muscle, but skip strenuous activity |
24–72 hours | Pain relief usually begins |
About 1 month | Typical length of relief |
After 1 month | If pain remains, more injections may be recommended |
Timeline from [1].
If you still have pain after this time, your provider may recommend more injections for longer-term relief. [1] Injections can also improve range of motion and how well the muscle works, depending on which muscle is treated. [1]
What are the risks of trigger point injections?
Trigger point injections are generally safe and carry a low risk of complications. Injections near the chest wall or upper back can rarely puncture a lung, so get emergency care for sudden chest pain or shortness of breath afterward. [1]
Type | Examples |
Most common side effect | Temporary discomfort or numbness around the injection site |
Rare complications | Bleeding, infection, bruising, allergic reaction to the anesthetic, injury to a vein |
Side effects and complications from [1].
When should you call a doctor after a trigger point injection?
Call your healthcare provider after a trigger point injection if you notice signs of infection, such as a fever or warmth at the injection site. [1] Also check back with your provider if your pain returns once relief fades, since more injections may help. [1]
Trigger point injections at a glance
Question | Answer |
What it treats | Myofascial pain from muscle knots (trigger points) |
Common areas | Neck, shoulders, arms, legs, lower back |
What is injected | Local anesthetic, with or without a corticosteroid or botulinum toxin |
Preparation | None; share your medicines and health history |
Setting | In the office; you go home the same day |
Relief starts | 24–72 hours |
Relief lasts | About 1 month |
Most common side effect | Temporary soreness or numbness at the site |
Call your provider | Fever or warmth at the injection site |
Summary of [1].
Conclusion
A trigger point injection is a common, generally safe way to calm a stubborn muscle knot that has not responded to pain relievers, heat, massage, or physical therapy. [1] The procedure can be briefly uncomfortable, but relief often starts within a few days and lasts about a month or longer. [1] It works best as part of a plan that includes stretching and physical therapy. [1]
If a muscle knot keeps coming back, talk with your healthcare provider about whether a trigger point injection fits your treatment plan. To understand what is behind the pain, read our plain-language guide to myofascial pain syndrome, and explore related guides on neck pain, back pain, and sciatica.
FAQ
What is a trigger point injection?
A trigger point injection is a shot into a painful muscle knot, called a trigger point, to relieve myofascial pain. The injection usually contains a local anesthetic, sometimes combined with a corticosteroid or botulinum toxin. [1]
Do trigger point injections hurt?
Trigger point injections can cause brief stinging, burning, or a short spike in pain when the needle reaches the knot. That short spike means the needle is in the right spot. [1]
How long does a trigger point injection take to work?
A trigger point injection usually starts to relieve pain within 24 to 72 hours. [1]
How long does a trigger point injection last?
A trigger point injection typically relieves pain for about a month. If pain remains after that, your provider may recommend more injections. [1]
What is injected in a trigger point injection?
A trigger point injection most often contains a local anesthetic, with or without a corticosteroid or botulinum toxin. Needling the knot with no medicine is called dry needling. [1]
What are the side effects of a trigger point injection?
The most common side effect of a trigger point injection is temporary discomfort or numbness at the injection site. Bleeding, infection, bruising, allergic reaction, and vein injury are rare. [1]
Can I go back to normal activity after a trigger point injection?
After a trigger point injection, you can go home and use the treated muscle right away. Avoid strenuous activity for the first few days. [1]
When should I call a doctor after a trigger point injection?
Call your healthcare provider after a trigger point injection if you have a fever or warmth at the injection site, which can be signs of infection. [1]
How often can you get trigger point injections?
It depends on how well they help and what medicine is used. Providers usually space injections out and limit how often they are given, especially when steroids are included.
Is soreness normal after a trigger point injection?
Yes. Mild soreness or bruising at the injection site for a day or two is common. Ice, gentle stretching and over-the-counter pain relievers, as advised, can help.
Related Reading
What Is Myofascial Pain Syndrome? A Plain-Language Guide to the Muscle Pain That Won't Quit explains the muscle pain condition that trigger point injections treat.
Dry Needling: How It Works, What It Treats, Risks and Recovery describes using thin needles without medicine to release muscle knots.
Myofascial Release Therapy: How It Works, What It Treats, and What to Expect covers a hands-on therapy that eases tight muscle and fascia.
Understanding Nerve Blocks: A Comprehensive Guide to Targeted Pain Relief explains injections that block pain signals from specific nerves.
References
Cleveland Clinic. Trigger Point Injections (TPI): What They Are & Procedure. Cleveland Clinic. Last updated July 26, 2022. https://my.clevelandclinic.org/health/treatments/17582-trigger-point-injection
Appasamy M, Lam C, Alm J, et al. Trigger Point Injections. Phys Med Rehabil Clin N Am. 2022;33(2):307-333. PMID 35526973. https://doi.org/10.1016/j.pmr.2022.01.011
Hammi C, Schroeder JD, Yeung B. Trigger Point Injection. In: StatPearls. Treasure Island (FL): StatPearls Publishing. Last updated July 24, 2023. PMID 31194353. https://www.ncbi.nlm.nih.gov/books/NBK542196/
Nouged E, Dajani J, Ku B, et al. Local Anesthetic Injections for the Short-Term Treatment of Head and Neck Myofascial Pain Syndrome: A Systematic Review with Meta-Analysis. J Oral Facial Pain Headache. 2019;33(2):183-198. PMID 30893405. https://doi.org/10.11607/ofph.2277
Navarro-Santana MJ, Sanchez-Infante J, Gómez-Chiguano GF, et al. Dry Needling Versus Trigger Point Injection for Neck Pain Symptoms Associated with Myofascial Trigger Points: A Systematic Review and Meta-Analysis. Pain Med. 2022;23(3):515-525. PMID 34114639. https://doi.org/10.1093/pm/pnab188
Ahmed S, Subramaniam S, Sidhu K, et al. Effect of Local Anesthetic Versus Botulinum Toxin-A Injections for Myofascial Pain Disorders: A Systematic Review and Meta-Analysis. Clin J Pain. 2019;35(4):353-367. PMID 30589660. https://doi.org/10.1097/AJP.0000000000000681
Medical disclaimer
This article is for general education only and does not replace professional medical advice, diagnosis, or treatment. Always talk with a qualified healthcare provider about your symptoms and before starting or changing any treatment. If you think you have a medical emergency, contact your local emergency services right away.
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