|Urushiol oil is pretty stable and can retain it's "potency" for years depending on conditions. It's not uncommon for people to infect themselves from gardening gloves, tools, etc. that came in contact with urushiol oil (from poison ivy, oak, sumac) weeks, months or even years previous.
That said - you do want to wash your clothes. A good detergent is recommended - Tide will certainly do. As the previous poster recommended - washing twice certainly won't hurt. Copious amounts of water and detergent are the key to getting the oil out of your clothes. Be very careful how you handle your clothes getting it into the washer.
I always wash my work clothes separate from my other laundry. It's part habit and part founded on the belief that I don't want to pass anything from one item to another.
Hope this helps.