Mathieu replied: "Firstly, I will correct the other two people and tell you what Lithium is used for. Lithium is FDA approved to treat bipolar and acute mania. It is also used for schizoaffective disorder, for severe treatment resistant unipolar depression (regular depression), and for cluster headaches if other treatments fail. Lithium definitely does not make people high or euphoric. Lithium is a naturally occurring element (Li) and a type of salt. . It was the first medication for bipolar disorder (aside from basically simply sedating patients with barbiturates). It has almost no noticeable psychotropic effects at normal doses. However it does have side effects, primarily mild hand trembling, a feeling like your head is in a "fog," and increased thirst (because it is a salt) and increased urination. Lithium is still considered the "golden standard" in treating bipolar. No other drug has been shown to be more effective. With many more mood stabilizers on the market lithium is not always the best option. But Lithium or Depakote are both first line and highly effective treatments for bipolar I. People with bipolar II are more often precribed a drug like Lamictal or Tegretol. And people with bipolar I will typically take an atypical antipsychotic and some people with bipolar II will also take an atypical. Lithium is the only mood stabilizer that is NOT an anticonvulsant. On important thing about Lithium is that if it is not monitored it can kill people surprisingly easily. The FDA has a black box warning (the most severe type of warning) because lithium can easily become toxic. When people take Lithium they must get regular blood tests especially when they first start. When the plasma (blood) concentration is 0.6 to 1.2 mmol Lithium/litre then the dose is in a safe and therapeutic level. But just a little bit more at 1.5 mmol Lithium/litre, it is toxic and can be lethal. I do not mean "over dose," I mean toxic which is a much worse thing. So simply put, unless the dose is fine tuned it can kill especially if it is misused. Before people knew how toxic is was and doctors just gave standard doses many, many people died. Symptoms of Lithium toxicity include tremor, ataxia (loss of movement control), nystagmus (involuntary eye movement), dysarthria (similar to aphasia consisting of difficulty articulating, uncontrolled movements), and gran mal seizures (even status epileptics, a consistent state of seizure). To make it even worse one person might take 1,200 mg/day and that would be a toxic dose yet another person might need 1,600 mg/day for it to help. If your friends were having any significant psychotropic effects they were either on multiple things or on a dangerously high level of Lithium. So not only is it dangerous, it is not addictive, it is not euphoric, and it is very bad to take unless you are under the care of a doctor."