What is the correct dosage for amoxicillin to treat uti in adults?

Depends!: Correct Amoxicillin dose for any infection depends upon sensitivity of bacteria causing infection. If bacteria is resistant to Amoxicillin or similar antibiotic, then it's a poor choice & won't work. That's why it's important to sent urine for c&s (culture & sensitivity). Btw, antibiotics like Amoxicillin only work against bacteria but not against virus which cause most common colds & sort throats.