Mrs 100th had a friend who took up road riding to keep fit and she really enjoys it but she is now giving up due to arthritis in her wrists. Anyone think of a way to keep her on the bike but not in pain?

Offroad = more upright, less weight on arms, said the bloke with a different arthritis problem.

As someone with arthritic hands I would recommend MTB with bar ends (they might not be fashionable but they allow a change of hand position). Suspension forks will also make life more comfortable.

Tri-bars?

also check bike fit is aimed at comfort not performance and that she’s not too far forward with all weight on wrists

Sounds like me minus the aching hands as well. MTBing doesn’t help actually, my hands work better on the drops. Fiddle with position to put more weight on arse.

Get someone to check her wrists are working properly – the actual wrist is only an inch or so long & has 2 rows of bones, so 3 rows of joints. Each row needs a certain ammount of mobility, otherwise the others overwork.
A short top tube & higher handlebars would also help.