Conditions that may present with generalised weakness
| Condition | Clinical clues |
|---|---|
| Guillain–Barré syndrome | Rapidly progressive ascending weakness |
| May involve respiratory muscles | |
| Loss of reflexes | |
| May have severe back pain | |
| Respiratory or gastrointestinal illness two to four weeks prior to onset | |
| Botulism | Symmetric descending weakness |
| Wound botulism | Cranial nerve weakness—for example, diplopia |
| Food borne botulism | No sensory symptoms |
| Prodromal nausea, vomiting, diarrhoea | |
| Suspect in intravenous drug users | |
| Spinal cord disease | Back pain |
| Sensory level | |
| Sphincter disturbance | |
| Motor neurone disease | Progressive weakness over months |
| Fasciculation of muscles | |
| Exaggerated reflexes | |
| May have bulbar involvement | |
| Vasculitic neuropathy | Painful |
| Multiple peripheral nerves affected (mononeuritis multiplex) | |
| Raised inflammatory markers | |
| May be associated with rash, arthropathy, renal disease | |
| Myasthenia gravis | Bulbar, ocular, and respiratory muscles affected |
| Ptosis | |
| Fatigability | |
| Viral myositis | Painful muscles |
| Raised creatine kinase | |
| Drug induced myopathy | Progressive proximal weakness over weeks |
| Myalgia | |
| Drugs history—for example, statins | |
| Metabolic disorders | Alcoholism |
| Hypokalaemia | Anorexia |
| Hypomagnesaemia | Drugs—for example, laxatives, diuretics |
| Hypophosphataemia | |
| Polymyalgia rheumatica | Elderly patient |
| Proximal pain and weakness | |
| Malaise | |
| May be associated with weight loss, headache, | |
| Raised ESR |