I quite understand your dilemma. My little girl is 2 and half and has just developed chicken pox, although it took a week to surface properly after a vague rash, which we thought was heatrash. She is one of the last ones to get it - most of her class have already had it. She timed it really well...'waiting' til the bank holiday, so haven't had to take any time off work yet, although we may need to juggle some days of between us next week. But obviously grandparents are a bit wary of looking after her for us, because of the shingles connection.
I am actually quite glad she has got it at last, to get it out of the way. But, she is now covered, with spots everywhere, including in her hair, and a couple on the inside of her bottom eye-lids, and one in her mouth. Quite hard to look at when their skin is usually so pure! But, she hasnt really had any fever etc and is pretty much on good form apart from feeling a bit more tired than usual.
Anyway, in answer to your question, here is where we are 3 days in!...
...I have bathed her with some oats, which has some healing properties for the itchiness, using a large handful of porridge oats in the leg of an old, but clean, pair of tights, knotted at one end. The oats secrete a milky fluid from through the material as they are left to soak in a warm bath. This helped soothe it.
...but, here is my suggestion for you - as the spots began to blister, the itchiness got much worse, last night, and in the end we turned to METANIUM cream, at my husbands suggestion, which we were recommended to use at the worst stages of nappy rash. It has an almost immediate effect in relieving the itchiness, and really drying out the blistering overnight, and calming down the angry redness. I would recommend it! It is much easier to apply that calamine lotion, being more of a cream than lotion, although the yellow colour does tend to come off on the clothes, but in my experience this does come out in the wash. It is good to know that you can use it in the genital area too, as its original purpose is a super-strong nappy rash cream. You can get it at most pharmacies/chemists, including Boots. Although not mention is made of chicken pox on the site, you can find out more info at www.metanium.co.uk
I have read here and there this morning that a few people seem to have found it a bit of a miracle cure, but I was unaware of it as a solution in general, until my husband suggested it.
There is also a slightly more gentle cream, with an oatmeal base, called Aveeno, which you can get in Boots, but was prescribed to me by my doctor, also for nappy rash, which I have used during the day, and will continue to use to soothe once the initial blistering has calmed down.
If you child is allergic to any thing, you might want to double check the metanium ingredients listing, if you haven't used it before.
I hope that helps!!