This is just my opinion on the matter but I feel quite strongly about it because I myself ended up developing contact dermatitis to tea tree oil.
Tea tree oil has pretty much one function post electrolysis and that is to prevent whiteheads. It does work. However it is also drying (you want moist skin before, during and after electrolysis) and can be an irritant hence my suggestion to give it a break for a bit to see if it is contributing. When it is used, it should be one drop (diluted - preferably purchased this way) on a cotton pad and dabbed. Once a day for about two days is more than sufficient.
There are other ways to keep whiteheads to a minimum and these all revolve around cleanliness. Having just last week had 10 hours of facial electrolysis over 4 days, this year I didn’t get a single whitehead. Last year, after the same treatment, I had a few. When I used to have electrolysis locally and it was only 15 minutes on my face (alcohol to clean the area first, tea tree immediately after), I’d always develop a few small whiteheads. Small whiteheads are probably the least evil post-electrolysis manifestation because they just last a few days and disappear on their own.
Aloe-vera will moisturise, cool and form a protective layer. The best whitehead prevention is to clean the area immediately after electrolysis with surgical soap and water. It should be verrrry gently dried with cotton and then a layer of aloe applied, again using cotton.
I do love witch hazel water and use it as a daily toner… it’s not essential post electrolysis but it is soothing.
My own experience with TToil - I used it religiously after appointments when I was seeing a local electrologist; once per day for about two days after treatment. 6 months into upper lip treatment I started to develop dryness and pigmentation in the area where one would have laugh-lines. It was actually my electrologist who alerted me to the fact that it might be caused by the TToil and recommended I stop using it. I did so for a while. Some months later I thought I would go back to it and a single use caused the most horrible skin reaction - swelling, redness and blistering. I was left with wrinkling and pigmentation in the laugh line area. This was 4 years ago, and it’s only this year that my upper lip (laugh line area) has started to show a full recovery, probably speeded along by my use of Retin-A this year. The pigmentation has gone and the lines have smoothed out.
http://www.consultant360.com/content/allergic-contact-dermatitis-tea-tree-oil
I completely accept that I am an individual case. My point is just to highlight that it is a strong chemical which I personally don’t feel is necessary in electrolysis after-care.