Will swelling/redness from poison ivy eventually go away on its own or is a course of steroids absolutely necessary? am hesitant to go steroid route.

Local steroids: Depending on the severity of the lesion, you may apply over the counter steroid ointment. You may not need to take oral steroids. Consult this site for information on this topic: http://www.mayoclinic.org/diseases-conditions/poison-ivy/basics/definition/CON-20025866 For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex.

Yes, can go : on its own, but will take time, depending on many factors: severity, location, complications, etc.. Steroids given under doctor's supervision, topically / systemically will be helpfull, if your doctor judges so, usually short course of prednisolone would help, together with other measures, follow your doctor's recommendations, good luck