Primidone (a.k.a. Mysoline, Lepsiral, Mysoline, Resimatil and others) is a commonly prescribed anticonvulsant (barbiturate) drug used to treat Epilepsyplugin-autotooltip__plain plugin-autotooltip_bigEpilepsy

"Epilepsy is a chronic noncommunicable disease of the brain that affects around 50 million people worldwide. It is characterized by recurrent seizures, which are brief episodes of involuntary movement that may involve a part of the body (partial) or the entire body (generalized) and are sometimes accompanied by loss of consciousness and control of bowel or bladder function. Seizure episodes are a result of excessive electrical discharges in a group of brain cells. Different parts of …, Essential Tremorplugin-autotooltip__plain plugin-autotooltip_bigEssential Tremor

"Essential tremor (ET, also referred to as benign tremor, familial tremor, or idiopathic tremor) is a progressive neurological disorder that is also the most common movement disorder. The cause of the condition is currently unknown.and other disorders. It has more than 2 million yearly prescriptions in the US alone.

It was first approved in the US in 1954, and since then, despite more than 60 years of medical research, its precise mechanism of action is still unknown.

It has been suggested that it works via interactions with voltage-gated sodium channels which inhibit high-frequency repetitive firing of action potentials in nerve cells. And that its breakdown products (as it's metabolised) may be responsible for its action.

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