Rapid breathing

Rapid breathing (tachypnoea) is breathing at a faster rate than normal. Breathing is finely controlled to keep oxygen and carbon dioxide balanced, so a faster rate is often the body responding to a need for more oxygen or to blow off excess acid or carbon dioxide. Common and often benign triggers are exercise, anxiety and panic (fast, sometimes shallow breathing, often with tingling and light-headedness), and fever. But rapid breathing is also an important sign of things that need attention: lung problems (asthma, a chest infection, or a blood clot in the lung), heart problems (heart failure), and a low blood oxygen from any cause. A distinctive pattern is deep, rapid breathing driven by acid in the blood — most importantly in diabetic ketoacidosis, where the body breathes hard to blow off acid (Kussmaul breathing). Rapid breathing is also one of the early warning signs of serious illness and sepsis. So while it can be a simple response, new, persistent or unexplained rapid breathing, particularly with breathlessness, chest symptoms or feeling unwell, should be taken seriously.

• Exercise or exertion — a normal response.
• Anxiety or a panic attack — fast, often shallow breathing with tingling and light-headedness.
• Fever or infection.
• Lung problems — asthma, a chest infection, or a blood clot in the lung (pulmonary embolism).
• Heart failure.
• Low blood oxygen — from any cause.
• Acid in the blood (metabolic acidosis) — deep, rapid breathing, classically in diabetic ketoacidosis.
• Sepsis — rapid breathing is an early warning sign.

The cause of rapid breathing is assessed clinically, with oxygen levels (a finger probe) and often a chest examination. Blood tests support this depending on the picture: bicarbonate and blood gases if acid in the blood is suspected (as in diabetic ketoacidosis), a lactate for severe illness or sepsis, glucose and ketones if a diabetic cause is possible, and a full blood count and CRP for infection. A chest X-ray and, if a clot is suspected, a D-dimer are used as indicated. Mediora.AI can surface a low-bicarbonate, high-lactate or infection pattern from your results that fits a serious cause, but new or severe rapid breathing needs prompt in-person assessment — especially with breathlessness or feeling unwell.