My daughter has deep venous thrombosis. Will this affect her health?

Compression. One of the best things your daughter can do, besides taking blood thinners, is to wear graduated compression stockings. She can decrease her risk of getting post thrombotic syndrome by 50% if she wears 30-40 mm hg, knee high, graduated compression stockings for 2 years after having her dvt.
I agree. With dr. Kopes-kerr. I would add that she is at risk for future clots as well, so depending on the circumstances, should have a low threshold for being evaluated for leg swelling (especially one sided) down the road and shortness of breath. Some people require life long blood thinners.
Deep venous clot. Deep venous thrombosis (as opposed to a superficial vein clot) should be treated with blood thinners like warfarin. If your daughter is appropriately treated and monitored for at least 3 months, there should be no serious long-term effects to her health. She may, however, develop persistent swelling, particularly in the legs, as the clot may damage the valves in the vein with resulting swelling.

Related Questions

My mom gets deep venous thrombosis, so am I likely to get it later?

Not likely. There may be genetic reasons your mom has clots. Usually blood clots like dvts are provoked by surgery or medicines, but if not or in certain other situations, then genetic testing might be done. If you knew this information, then you'd be more likely to get a blood clot too, but still this would not be a likely event.
Possibly. If your mom got a blood clot for an identifiable reason, then you probably don't have to worry. If, on the other hand, she got a blood clot for reasons that are unclear then she should have blood tests to see if there is a genetic reason (thrombophilia) why the clot occurred. If any of the tests are abnormal, then you should probably be tested too since some thrombophilias can be hereditary.