Time travel, LSD, paradox, alternate history?

[Jungleboy]

Looking for a book with the following story line.
A time traveller (Cop? Tourist Guide? Spy?) spend most of his time in the middle ages with his (there in that time) love interest, but also has one in 300.000 AD.
The way the time travel works is explained (with graphics) like woking as LSD capsules that cause an 'implosion' (of sorts) this opens access to reality 'membrames'
Due to some (mistake?) he appears in the exact same time line as an earlier version of himself and causes a paradox.. now he has to share the girl with himself ( he is now called [name]A & [name]B )- in the end somehow he gets trapped in the far future - ne
- I know it is a bit out there.. but I read this book in the early 80's - I remember the writer being from Belgium(?) and that it contained graphics/illustration as an aid to the normal writing
the back of the book had a full time line of occurence (alternative)
It also explained how history has been altered by time tourism

I hope someone can help?
tried alibris.com - to no avail. nothing on the combination of LSD + paradox (which should be understood and searchable in both Dutch & English) - I cannot recall if this book was in Dutch or English - but I prefer an English edition ... If I ever will be able to locate this..