What is the best option to get a large varicose vein removed for a 25 yr old?

Surgery: A general or vascular surgeon can safely remove a varicose vein, sometimes in the office.

Various treatments: You need to start with an evaluation by a phlebologist, including an ultrasound examination (which must be done with you standing). There are a variety of minimally invasive techniques which can treat varicose veins, but a proper treatment plan needs to be developed based on the exam and ultrasound. Ligation and stripping is obsolete.

Ultrasound first: As dr. Worthington-kirsch said, the start of good treatment for a large varicose vein is a standing ultrasound exam of your veins. You should be a vein specialist (phlebologist) to have this done. Your treatment course will depend on the results of the ultrasound and your phlebologist will discuss your treatment options with you.

Young veins: For someone this young, the source and location of the vein is vital. A vein specialist should perform a physical exam and a duplex ultrasound. Large veins on the inner calf are completely different than running down the lateral leg (which could be a malformation like klippel trenaunay syndrome) and require very different approaches and levels of expertise.