The links in the left margin point to explanations of remedy relationships on the forum. For a full explanation, please see those threads. Here though is a summary of the terms used:
Antidotes The remedies are antidoted by the stated remedy, when given in homeopathic doses.
Chemical AntidotesThe remedy antidotes poisoning by these remedies. These are included for completeness, but if you suspect you, or anybody, has been poisonned, you'll obviously be seeking immediate professional medical advice.
Cognates / Similar / CompareSimilar remedies for comparison purposes
ComplementaryThese remedies work well in pairs, with the second remedy given later to finish what the first has started.
Inimical / incompatibleThese remedies should not be taken one after another.