Antihistamines are fine....I am NOT anti histamine, but to take a tablet for itchy eyebrows with it's side effect on the body, when a little cream with no side effects will do the trick....seems to remind me of a "sledgehammer to crack a nut."
check out blepheritis (sp?) Tilly - I've been diagnosed with it but the NHS stuff didn't work for me , was very harsh - got some stuff from my optician which was much better. Try bathing eyes each morning with a warm cloth, it really helps.
Sqad has been absolutely right to recommend 1% hydrocortisone. It would be my choice too as it's fairly mild in action. The other thing you could try is E45 Itch-Relief cream which is urea based and even milder. It worked for me when I had this problem a few years back.