Almost all religions observed that life is a suffering and provided means to end the human suffering by doing some prayer or penance. Most philosophers also ,I guess, recognize that life is a suffering.
However from philosophical point of view , have we come up with a theory to end human suffering other than by taking drugs or medicines?
As you already know, being a user on Buddhism.SE, that (i.e. ending suffering) is the central theme of the Buddhist doctrine, for example as it's described in many of the suttas of the Pali canon.
To address the comments, just while I'm here:
I don't know why this comment said "Have the world consist only of philosophers" ... was that serious, is it a joke, is it because philosophers are inoffensive, or immune to suffering? :-)
This comment said that some people "are tormented by envy" -- that (envy) is one of the many types of suffering that Buddhism has a presciption for: for example it's one of the five afflictive emotions in Mahayana; and/or the Brahmaviharas including mudita are proper social emotions.
I don't know much about Western philosophy (perhaps I came to this site with the same question that you did, which is how I found your unanswered question here).
I think that maybe Stoicism has some obvious paralells with Buddhism. One disadvantage, perhaps, is that there isn't much surviving literature from the early stoics (compared to e.g. the whole bookshelf, the whole library, of Buddhist literature), though there's more from some of the later stoics like Marcus Aurelius (I'm not sure whether Marcus Aurelius should be considered a good teacher though, or whether instead perhaps he was a good student).
I looked at Wikipedia's Categories in the hopes of getting an overview or introduction or index. Within those categories:
It seems to me that "metaphysics" is kind of abstract and useless. I guess an example of metaphysics is this question: If a tree falls in a forest. IMO Buddhism sort of avoids the problem by telling you to concentrate on what you perceive (e.g. "contact between sense-organ and sense-object and sense-consciousness gives rise to perception and feeling etc.").
Does Buddhism's focus, on what does or doesn't cause suffering, exclude a lot of abstract metaphysics?
"Value theory" sounds like it ought to be interesting -- it includes ethics (virtue) and asking "what is 'good'?" But, I guess it may get side-tracked though: into economics, consumerism, and more metaphysics.
This says about "Ethics" (which is categorised as a sub-topic of "Value theory") that,
A major area of debate involves consequentialism, in which actions are judged by the potential results of the act, such as to maximize happiness, called utilitarianism, and deontology, in which actions are judged by how they adhere to principles, irrespective of negative ends.
So, according to that, something in "utilitarianism" might be interesting, relevant to "ending human suffering", if it's teaching how to maximise happiness? Or maybe it's more samsara. :-)
Writing this answer reminds me of Zen and the Art of Motorcycle Maintenance ... in which, about two thirds of the way through the book, the protagonist becomes angry to discover that "What is good?" is not considered the central question of philosophy, but was somehow demoted by Aristotle to a sub-sub-category, of "logic" or something like that.
David Benatar proposes antinatalism, and the 'benevolent world-exploder' view. While Buddhism proposes an end to suffering only for those who attain enlightenment, Benatar's view could potentially end suffering for all humans in our lifetime.
Stoic philosophy aims to end avoidable suffering, by focusing on what you can change, and resigning yourself to what you cannot.
