I'm sorry to hear that your dry cough has persisted for several months despite treatment. A cough lasting more than 8 weeks is considered chronic and can have various causes such as allergies, asthma, gastroesophageal reflux disease (GERD), chronic bronchitis, or other underlying conditions.

Here are some important steps you can take:

• See a specialist doctor, preferably a pulmonologist (lung specialist) or an ENT (ear, nose, and throat) doctor, for a thorough evaluation.
• They may recommend investigations like chest X-rays, lung function tests, or allergy testing to identify the cause.
• Since your cough temporarily improves with medicines like Benadryl Cough Formula Syrup (which contains expectorants and antihistamines), but then returns, it suggests the underlying cause may not be fully addressed.
• Avoid irritants such as smoke, strong perfumes, or allergens that might worsen your cough.
• Keep well hydrated and avoid self-medicating for prolonged periods without medical advice.

Persistent dry coughs require careful assessment to rule out serious conditions and to tailor treatment effectively. Please consult a pulmonologist or ENT doctor soon for a detailed examination and appropriate management. If you experience worsening symptoms like difficulty breathing, chest pain, or coughing up blood, seek emergency care immediately.To narrow down potential causes, we will need some more information.I understand that you have been having a cough for the last 4-6 months and it is not improving with medicines. Please tell me your age and gender.