General Red Flags

• Unexplained Weight Loss: Significant, unintentional weight loss can indicate malignancies, chronic infections, or endocrine disorders.
• Fever of Unknown Origin: Persistent fever without an obvious source can signal infections, malignancies, or inflammatory diseases.
• Severe or Persistent Pain: Pain that is severe, persistent, or not responding to typical treatments can be a sign of serious underlying conditions.
• Night Sweats: Especially when associated with weight loss and fever, night sweats can indicate infections, malignancies, or hormonal imbalances.

Cardiovascular Red Flags

• Chest Pain: Sudden, severe, or persistent chest pain, especially if radiating to the arm or jaw, can indicate myocardial infarction.
• Shortness of Breath: Unexplained or sudden onset of dyspnoea can be a sign of pulmonary embolism, heart failure, or other serious conditions.
• Syncope: Sudden loss of consciousness can be associated with cardiac arrhythmias, structural heart disease, or significant hypotension.

Neurological Red Flags

• Severe Headache: Sudden, severe headache, often described as "the worst headache of my life," can indicate a subarachnoid haemorrhage.
• Neurological Deficits: Sudden weakness, numbness, or difficulty speaking can be symptoms of stroke or transient ischemic attack (TIA).
• Seizures: New-onset seizures or a change in seizure pattern can indicate central nervous system pathology.

Gastrointestinal Red Flags

• Rectal Bleeding: Blood in the stool can be a sign of gastrointestinal malignancies or severe inflammatory conditions.
• Severe Abdominal Pain: Pain that is intense and localized, particularly if associated with fever and hypotension, can indicate acute abdomen conditions such as appendicitis or bowel perforation.
• Dysphagia: Difficulty swallowing can suggest oesophageal cancer or significant motility disorders.

Respiratory Red Flags

• Haemoptysis: Coughing up blood can be a sign of lung cancer, tuberculosis, or severe infections.
• Persistent Cough: A chronic cough, particularly with weight loss and night sweats, can indicate tuberculosis or lung malignancy.
• Sudden Dyspnoea: Acute shortness of breath can be a sign of pulmonary embolism, pneumothorax, or severe asthma exacerbation.

Musculoskeletal Red Flags

• Back Pain with Neurological Symptoms: Back pain accompanied by numbness, tingling, or weakness in the legs can suggest spinal cord compression or cauda equina syndrome.
• Joint Swelling and Redness: Swollen, red, and warm joints can indicate septic arthritis or severe inflammatory arthritis.

Urinary Red Flags

• Haematuria: Blood in the urine can be a sign of urinary tract malignancies, stones, or severe infections.
• Severe Flank Pain: Pain radiating from the back to the groin can indicate kidney stones or pyelonephritis.

Dermatological Red Flags

• Non-healing Ulcers: Chronic, non-healing skin ulcers can be indicative of malignancies or severe vascular disease.
• Rash with Systemic Symptoms: A rash accompanied by fever, joint pain, or other systemic symptoms can indicate autoimmune diseases or severe infections.

Paediatric Red Flags

• Failure to Thrive: Inadequate weight gain or growth in infants and young children can indicate underlying medical or social issues.
• Persistent Vomiting: Frequent, forceful vomiting in infants can be a sign of pyloric stenosis or other gastrointestinal obstructions.
• Lethargy and Irritability: Unexplained lethargy and irritability in children can signal serious infections or metabolic disorders.