How can I clean my electric toothbrush?

[MackerelOfFact]

However much I try I can't get the electric toothbrush (the unit you hold, not the brush attachments) clean. It has a build-up of white, either limescale or toothpaste or a bit of each, between the ridges in the rubber and basically looks a bit grim. I've tried spraying it with bathroom cleaner and leaving a few minutes but it didn't really do anything. I'm wary of destroying the rubber if I use anything too harsh. Temped to stick it in the dishwasher but not sure if it would survive.

Any ideas how I might get rid of the grime without wrecking it?

I'd go for bathroom spray cleaner and a toothbrush. Trouble is that water can get in through the base sometimes and corrode the internal connections. I've had that with a Braun/Oral B. This is less likely to happen if you keep it upright rather than putting it in the sink like I did.

It can also be dried-up saliva and toothpaste, which you can get of by repeatedly sponging with warm water (soft water is better). It goes slimy which is revolting.

The head can be put in denture cleaner or the dishwasher

I think you'll know, in future, to stop it getting so bad sorry. e.g. sponge it down with WUL every day or so when cleaning the bathroom

denture tablets.
just put the brush upside down in a mug with warm water and add one or two denture tablets. leave over night, then rinse.
to reduce build up rinse and towel dry after use.

Thanks for the suggestions, I didn't think the dishwasher would be the way to go but I was tempted last night! I'll definitely try denture tablets. I do rinse it after every use to limit buildup and stand it upright when not in use but we're in a very hard water area which is probably part of the problem. Towel drying would help.

I had a Phillips Sonicare... till I put it in the dishwasher. So you'll do well to avoid that. Would work for the head though, I think. I got another (cheaper) one as I have trouble with my gums and dentist recommended it. Have been battling with the cleaning thing this week. Took the head off the base and stood the head with the magnet (?) side down and the base upside down in a small cup of bleach for several hours. This seems to have worked quite well.

Denture tablets are a genius suggestion.