Brief Answer:
VPA's side effects likely less well tolerated & can be as dangerous too

Detailed Answer:
Many thanks for your return query regarding VPA (Valproic Acid) as an option to using Keppra and Vimpat.

I think you fairly have referred a VERY GOOD question and comparing a drug which is time tested and well known to practitioners (neurologists and non alike) more so than Vimpat or Keppra. However, truth be told, even though VPA is a more time tested type of drug the fact is...side effects of this medication have never been well liked by anybody who either takes or prescribes the drug. It can easily cause mental status issues and blood dyscrasias much more quickly and extensively at relatively lower doses than the other 2 medications under discussion.

I find that our epileptologists both at the VA as well as outside institutions are choosing VPA less and less as their drug of choice in patients with partial seizures. VPA still remains the GOLD STANDARD in JUVENILE MYOCLONIC EPILEPSY and similar syndromes even if not in juveniles but there is no accepting that the drug must frequently be monitored so that its blood levels don't get out of range (in either direction..meaning too high or too low) and that bone marrow function isn't unexpectedly or suddenly depressed as can happen even in individuals who have been taking it for many years. Sometimes there is either an environmental or chemical that causes things to inexplicably go off the rails so to speak. Then, getting patients back on the right track can be tricky. There are also unwanted side effects such as excessive weight gain, tremors that occur, and VPA has a plethora of drug to drug interactions that KEPPRA entirely avoids with VIMPAT coming in as well with less frequent reactions.

My experience between Vimpat and VPA is that VPA tends to control seizures more effectively than VIMPAT, however, gram for gram, I believe that side effects are more troublesome with VPA compared to VIMPAT (or Keppra for that matter).

My prediction over the next 5-10 years is that VPA is going go more into the background as a seizure control medicine and find more of an acceptable role in psychiatric cases of anger management, behavior dyscontrol in patients with dementia or schizoaffective types of disorders as well as treating manic states and certain forms of anxiety. I believe it is going to find more of a role in these functions as more and more drugs similar to Keppra and Vimpat come out of the pipeline which address less egregious side effect profiles and become even more efficacious at lower potencies.

If I'm wrong in the next 10 years...well, hopefully, enough of my kids will have moved out and I'll have found enough time to visit the Galapagos Islands enough to know I'd prefer not to come back to find out I was wrong in my prediction...so I'll never know! LOL!

So I guess the bottom line is that VPA is still not a bad drug to use but if given the choice between Keppra and Vimpat I would prefer of those agents than the VPA. If either of those drugs failed to show initial or satisfactory efficacy then, I might consider trying VPA as a 2nd line drugs. Otherwise, I hardly if ever recommend it as FIRST LINE anymore where Keppra or Vimpat would be expected to function as control meds.

My biggest concerns with VPA are its not so good reputation in interacting with many many other common drugs as well as the fact that it can cause mental, physical, and biochemical side effects that can be more severe than at first glance and not easy to bounce back from once they've been initiated without a solid washout period of at least a couple of weeks before starting anything new.

I would definitely choose KEPPRA over VPA for efficacy and safety...whereas I may choose VPA over VIMPAT for efficacy in PARTIAL SEIZURES but choose VIMPAT over VPA for overall safety and numbers of side effects. VPA may have a bit of an edge compared to VIMPAT or KEPPRA in terms of better utility to treat psychiatric symptoms but even in that instance there are a number of specific psychiatric medications which have come out to serve in that role without having to necessarily rely on VPA to entirely do the job.

I am hopeful that you will be able to find something that can adequately be used for partial seizures from the information I've provided.

I do hope this information has given you some additional perspectives on a satisfactory AED to choose in the field of VIMPAT and KEPPRA and hope you can point some of that information to good use to make the best decision for yourself.

This query has required 33 minutes to research, investigate, and prepare a response.

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