Dizziness is a very common side effect of tamsulosin. This is seen in early stage of treatment and often resolves with progress of time once you become accustomed to it. Other side effects of tamsulosin are orthostatic hypotension, syncope, headache, infection such as pharyngitis, asthenia, back pain, somnolence, and insomnia. These will resolves once you become accustomed to tamsulosin. Advice 1. Continue tamsulosin as suggested by your doctor. Take it with food. Take ½ hour following the same meal daily 2. Take rest for few days 3. Give him a glass of salt water to drink he feels hypotension and dizziness 4. Avoid driving, swimming, strenuous physical activities and operating machinery if any 5. Drink 4 – 5 liters of water daily I hope this information will help you. I will be happy if you ask another question Thanks