Hello, Welcome to HCM and thanks for your query. Lithium is a good drug to prevent episodes of depression in you. It is relatively safe if in the safe therapeutic blood levels. Lithium can cause nausea, diarrhea, dizziness, muscle weakness, fatigue, and a dazed feeling. These unwanted side effects often improve with continued use. Fine tremor, frequent urination, and thirst can occur and may persist with continued use. Weight gain and swelling from excess fluid can also occur. Lithium can also cause or make skin disorders such as acne, psoriasis, and rashes worse. It is not a medicine producing addiction but may require to be used continuously to avoid relapses of depression. Take care Dr Noble Zachariah