What is the best treatment for laxed and wrinkled skin on forearms?

Thank you for your questions regarding forearm skin wrinkling which is just
beginning to show. Forearm skin wrinkling is not an uncommon problem. Typically,
this is due to aging skin and sun exposure. Conservative treatments include
Thermage. If the skin wrinkling becomes severe, you may need a forearm
reduction. During a forearm reduction, excess forearm skin is directly excised.
When considering a forearm reduction, please seek an experienced,
board-certified plastic surgeon with years of experience. I hope that I have
answered your question, if you have any more questions regarding forearm
reduction, please call my office.
Sincerely,
Dr. Katzen

Most likely, you will find non-surgical treatments are the way to go for the forearm area. Treatments such as Sculptra and lasers can be useful. Not many surgeons offer operations for this area. Best wishes. Dr. Aldo

Hello!!
Thanks for the question and provided information as well. 
Without pictures it is hard to give you a recommendation. 
I recommend you to make an appointment with a board plastic surgeon for a good evaluation and to talk about your goals.
Good luck :)