The term "drain of resources" implies an excessive use or consumption of resources that results in depletion or exhaustion. A possible synonym for this phrase could be "resource depletion," which signals that the resources have been used up and are no longer available for use. Another alternative might be "resource exhaustion," which suggests that the resources have been completely used up and cannot be replenished. A third option could be "resource depletion syndrome," which encompasses the idea of resource overuse and depletion as a recurring pattern that leads to negative outcomes. Overall, using different synonyms for "drain of resources" allows for a more varied and descriptive language use when describing the unsustainable use of resources.