A persistent cough is your body's signal to check in with a clinician, especially if it lasts longer than a few weeks or is accompanied by red-flag symptoms. Here’s a practical guide to help you decide when to see a doctor and what to expect. Direct answer

• See a doctor if your cough lasts longer than 3 weeks (persistent cough) or if it’s worsening, or you notice any red-flag symptoms. If you have ongoing breathing difficulties or any concerning signs, seek medical care promptly. If the cough is associated with fever, coughing up blood, wheezing, chest pain, or unexplained weight loss, contact a healthcare provider sooner rather than later.

Key signs that warrant medical attention

• Cough lasting more than 3 weeks (or 4 weeks in some guidelines)
• Shortness of breath, wheezing, chest pain, or coughing up blood
• High fever or night sweats
• Cough with green/yellow phlegm, persistent fatigue, or unintentional weight loss
• In people with underlying lung disease (e.g., COPD, asthma) or immune compromise, a coughing change should prompt evaluation sooner

Which doctors or settings to consider

• Primary care physician or family doctor for a first evaluation
• Urgent care if the cough is accompanied by significant shortness of breath or you need quicker access
• In children, seek care if the cough is associated with trouble breathing, high fever, drooling, or dehydration

What to expect at the visit

• Medical history review: onset, duration, exposure (ill contacts, smoking), accompanying symptoms (fever, night sweats, weight changes)
• Physical exam focusing on lungs, throat, and possible signs of infection or asthma
• Possible tests: chest X-ray if pneumonia or other lung issues are suspected; throat swab or blood tests if an infection or other condition is suspected
• Treatment depends on cause: hydration, cough suppressants or expectorants for symptom relief, antibiotics if a bacterial infection is suspected, inhalers if asthma or COPD is involved, or investigations for chronic conditions if the cough persists

Self-care steps while you consider care

• Stay hydrated and rest; humidified air can ease throat irritation
• Try honey for soothing cough (avoid in children under 1 year)
• Avoid smoke exposure and other lung irritants
• Over-the-counter remedies may help short-term but aren’t substitutes for medical evaluation if red flags are present

If you’d like, share your age, any accompanying symptoms (fever, shortness of breath, chest pain, cough duration), and whether you have underlying conditions. I can tailor more specific guidance on when to seek care and what to discuss with your clinician.