I found that the low dosage of aspirin (100mg/daily) has helped but when it flairs up again, I also use an antihistamine like loratadine.

Zyrtec!

Hi, I have ET and found that after showering I itched like crazy for about 25 mins, I found that if I patted myself dry it wasn’t anywhere near at bad, seems that rubbing myself with a towel aggravated the symptoms

Hello from Los Angeles. I've been dealing with Cal R mutation ET since 2020.
I'll add: If it's a small itchy spot, it helps me to put on anti-itch cream or cortisone cream and cover the spot with a Bandaid so the cream doesn't rub off quickly. In the shower, avoid deodorant soap like Zest. Dove soap is better, but best for me are the Aveeno moisturizing body wash products such as Skin Relief or Stress Relief (that one has lavendar so it smells good).

Some things I’ve found help annoying itchy skin…
-NY Biology tea tree body wash
-Aveeno oatmeal bath packets
-Cortisone anti itch cream
-and very powerful relief from having hair dryer on warm and/or hot pointing at the itching spots.

The hair dryer one brings great relief and feels good like you’re scratching the itches without messing up by scratching. Lol.