Acute painful muscle spasm

Sudden painful skeletal-muscle contracture, most often in the neck, back, or lumbar region. Usually triggered by overexertion, cold exposure, or awkward movement. NICE 2020 and SER 2022 ground treatment in continued activity within tolerable limits, local heat, and short-course paracetamol or NSAIDs. Centrally acting muscle relaxants (thiocolchicoside, cyclobenzaprine) are reserved for short courses up to 7 days in marked contracture; the benefit-risk balance shifts toward harm in patients over 60.

ICD-10 M62.82 drugs

Also known as: Acute muscle contracture, Painful muscle stiffness

Drugs used for this condition

CThiocolchicosideAdd-on therapy · Centrally acting muscle relaxantAdd-on therapy for acute painful skeletal muscle spasm in adults over 16, alongside analgesics. Per the 2014 EMA decision, oral courses are limited to 7 days (8 mg twice daily) and IM courses to 5 days (4 mg twice daily). Evidence versus other muscle relaxants is weak; placebo advantage is modest (Tüzün 2016 meta-analysis).

Marketing claims without evidence base

The drug is promoted for these uses outside international guidelines. Each entry below is analyzed against AEMPS, FDA, EMA, Cochrane and major RCTs.

DTolperisoneNot recommended · Centrally acting muscle relaxantIn Russia tolperisone is prescribed for painful muscle spasm in the back and neck, often alongside an NSAID, and it is registered for that. In the European Union the indication was removed: in 2012 the CHMP reviewed every tolperisone indication and kept only post-stroke spasticity in adults. The reason lies in data quality: studies from the 1960s and 1970s fall below today's standard, and the material on locomotor diseases, vascular diseases, rehabilitation after surgery and Little's disease was called limited and unconvincing. The second reason is safety: more than half of the spontaneous adverse reaction reports were hypersensitivity reactions, from skin rash to anaphylactic shock, while trials had shown almost none. Injectable forms were revoked across the EU. One practical point stands apart: the label states that tolperisone potentiates niflumic acid, and with concomitant use the dose of that or another NSAID is reduced. If tolperisone has been prescribed as a course for back pain, consider seeking a second opinion.

How to read tiers A–F

Evidence tiers belong to the drug-indication pair, not to the drug as a whole: the same substance can be A for one condition and F for another.

AStrong evidence – first or second line in international guidelines
BRecommended in selected cases
CStudy data contradict each other
DBenefit not proven, no documented harm
FDocumented harm, or risk without benefit