Which symptom is commonly associated with the use of anti-convulsants?

The commonly associated symptom with the use of anti-convulsants is nausea. Nausea can occur as a side effect due to how these medications interact with the central nervous system and gastrointestinal tract. Many anti-convulsants can irritate the stomach lining or affect neurotransmitters that influence nausea, leading to this common side effect in patients who are beginning treatment or adjusting their doses.

Weight gain can also occur with certain anti-convulsants, but it is not as universally recognized as nausea, which tends to be reported more frequently. Similarly, increased energy levels and improved memory retention are not typical effects of anti-convulsants; in fact, sedation and cognitive impairment can sometimes be observed instead. Thus, among the options provided, nausea stands out as the most expected symptom associated with anti-convulsant use.