Statin-associated muscle symptoms (SAMS)

Accessible web versions of NPS MedicineWise Statins clinical tools, SAMS Assessment Guide and SAMS Management Algorithm

Use a systematic approach to assess suspected statin intolerance

Figure A: Tolerability of statin treatment1
  • Statin intolerance is rarely life-threatening and may have a lower incidence than is commonly reported.2-4
  • Statins have been associated with a nocebo effect, whereby patients experience adverse effects based on the expectation of harm from a treatment.5
  • For muscle-related adverse effects:
    - Incidence of statin-associated myalgia is lower in blinded RCTs (1% to 5%)6 compared to observational studies (7% to 29%).4
    - Myopathy incidence is ~ 1 in 10,000 per year.4
    - Rhabdomyolysis incidence is ~ 1 in 100,000 per year.4
  • Involve the patient in assessing and managing adverse effects.
  • Advise patients to contact you if they experience muscle symptoms, and not to stop taking their statin.6

SAMS Assessment Guide

SAMS Assessment Guide, created by NPS MedicineWise 2017
See accessible text version of this table below

SAMS less likely SAMS more likely
Non-specific distribution
Tingling, twitching, shooting pain, nocturnal cramps or joint pain
Nature of symptoms4,6,7 Bilateral
Large muscle groups (eg, thighs, buttocks, calves, shoulder girdle)
Muscle ache, weakness, soreness, stiffness, cramping tenderness or general fatigue
Onset before statin initiation
Onset > 12 weeks after statin initiation
Timing of symptoms4 Onset 4-6 weeks after statin initiation
Onset after statin dosage increase
Non-statin causes of muscle symptoms including:
  • conditions eg, hypothyroidism, polymyalgia rheumatica
  • vitamin D deficiency
  • unaccustomed/heavy physical activity
  • medicines eg, glucocorticoids, antipsychotics, immunosuppressant or antiviral agents
Other considerations4,7
Risk factors for SAMS including:
  • medicine or food interactions
  • high-dose statin therapy
  • history of myopathy with other lipid-modifying medicines
  • regular vigorous physical activity
  • impaired hepatic or renal function
  • substance abuse (eg, alcohol, opioids, cocaine)
  • female
  • low BMI

CK levels4
Elevated (> ULN, but may also be normal)
Elevated CK levels decrease after statin ceased.

SAMS Management Algorithm

SAMS Management Algorithm created by NPS MedicineWise 2017.

Read an accessible text version of this flowchart