Brief Answer:
Rapid urination and/or dehydration.

Detailed Answer:
Hi,
Thank you for using Healthcare Magic. Foamy urine is usually associated with protein in the urine but I note you do not have protein. Therefore, I suggest that the appearance of your urine may be due to rapid urination with a full bladder. This can cause the appearance of foam Also, dehydration may be factor. You do not always feel thirsty when dehydrated. Thirst is a late sign of dehydration.
Therefore, initially I suggest you empty your bladder more frequently if possible and drink plenty of water to ensure good hydration.
Even though you have detected no protein, there is still the possibility of infection but this is usually accompanied by pain on urination. If these simple measures produce no improvement, I suggest you see your doctor as it would be advisable to have further investigations to rule out kidney disease or a fistula.
I hope this is of help. If you have any further questions, please do not hesitate to contact me.
Regards,
Dr K A Pottinger,
MBChB FRCA

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