lamotrigine and no appetite..?

[DexysMidnightRuner]

So my friend contacted me about a problem she is having. She has been prescribed Lamotrigine 150mg. Every time the dose goes up, she can not eat. I took a quick look on google and on here, but haven't found much. I know it triggers your sodium channels and your 5-ht3 receptors but neither of these should effect you're appetite. Any ideas?

 

[DexysMidnightRuner]

Is it just because it accesses the 5ht3 receptor? Since 5ht receptors are serotonin receptors? and serotonin affects appetite?

 

[sekio]

I don't think it can be rationalized that way, no... related drugs that are 5ht3 antagonists are anti-nauseants and in the case of something like mirtazepine are generally appetite increasers.

It's likely related to the sodium channel blockade (sodium channels are a very broad class of cellular receptor), which is also what produces the anticonvulsant/mood stabilizing effect. So she may need to switch meds or find something that will help her appetite. Weight loss is a reported side effect of lamotrigine, so it's not like this is an unknown response.

 

[DexysMidnightRuner]

true true. Do you know how the sodium channels actively affect you're appetite?

 

[sekio]

I don't think there's an obvious mechanism for sodium channels to effect appetite. They're a very generalized type of cell receptor.

I think your friend should talk to their doctor.

 

[DexysMidnightRuner]

Thats basically what I found. Thanks. And she has been, but she wanted a second opinion.

 

[MyExcuse]

You mentioned that she experiences this whenever they increase the dose. I'm assuming she's still titrating to 200mg daily?

Either way, tell her to try taking her meds at night if she's taking them in the morning.

I also highly recommend a folate supplement, 5-methyl-folate in particular. Some of the side effects can be ameliorated by a higher dose folic acid supplement. Lamotrigine was discovered because researchers were testing out anti-malaria drugs that acted as folic acid "antagonists".