It means this:
do not take any of the aforementioned substances 2 hours before you take 'this medicine', and don't take any of the aforementioned substances within 2 hours of taking 'this medicine'. That means that you have to go for 4 hours without taking any of the aforementioned substances. Which seems to me to be daft advice.
It may seem daft to some people, but it's to ensure that "this medicine" isn't adversly affected by those things....for example, they could prevent proper absorbtion of the medication.
It's a pain but necessary. If I need to take peppermint oil tablets, I have to take them 2 hours before or after my PPI tablet, Lansoperzole. Then after taking the latter, have to wait 30 minutes before I have cup of tea and breakfast in the morning.
I get told I should take some tablets at a different time to when I take a load of other tablets , but its just occurred to me that when I am in hospital I am given all my tablets at once no mention of waiting a couple of hours !
I haven't said much as not much to say but am in regular contact with Mrs Sqad. Unfortunately he remains in hospital with various complications related to his diabetes. I keep hoping she'll say he's coming out but they don't seem to be able to get his problems under control. She's going to see him daily and by all accounts they have had some interesting discussions with the staff :-) I'm pleased to note that he is looking in on AB but clearly doesn't want to post at the moment.