test questions, please clarify

i had a test and a couple of questions are bugging me. please can anyone clarify? i would appreciate it, thanks!

the questions are:

1. which of following accurately describes the physiologic action of carbamazepine?

a) alters sodium and calcium channels

or

b) increases gaba activity and blocks sodium and calcium to stop action potentials.

my reasoning was, carbamazepine is used to treat general seizures( tonic clonic, simple and complex) and therefore stabilizes nerve membrane by blocking channels in the cell membrane. so i chose "a"

most of my classmates think it is "b"

2.an 8 yr old has been diagnosed with seizure disorder and phenytoin (dilantin) has been prescribed for him. which of the following nursing diagnosis would be appropriate?

a) deficient fluid volume

b) impaired oral mucous membranes

c) non compliance for drug therapy

d) sleep deprivation

i chose "a" becuse dilantin can cause gingival hyperplasia. but again i was debating if it was "c".

3. expected outcome for a patient taking levadopa for parkinson's disease

decreased rigidity

or

decrease in muscle twitching

i chose decreased rigidity.

please clarify, thanks again!

for #1, i'm thinking i would go with a as well.

for #2, i'd choose b, because of the gingival hyperplasia. in fact i just consulted w/ my davis drug guide and it lists b as a possible diagnosis.

for #3, i'm not sure. i couldn't decide so i consulted davis again, and it says "relief of tremor and rigidity in parkinson's syndrome". still a tough call, lol, but i suppose i'd choose decreased rigidity.

Thanks for your reply. I am sorry I meant "b" for #2 question. Sometimes not knowing which one is the answer really kills you!

I didn't look at your answers when making my selection and here's what I chose:

1. A

2. C but thinking now it's most likely B due to gingival hyperplasia

3. muscle twitching - Parkinsons patients have difficulty with fine motor movements so Levodopa helps control twitching. Rigidity is what can happen in last stage Parikinsons and also a side effect of long term Levodopa therapy, remember dyskinesia is a side effect?

These were kind of tricky! And it has been over a year since I learned this material. :)

I didn't look at your answers when making my selection and here's what I chose:

1. A

2. C but thinking now it's most likely B due to gingival hyperplasia

3. muscle twitching - Parkinsons patients have difficulty with fine motor movements so Levodopa helps control twitching. Rigidity is what can happen in last stage Parikinsons and also a side effect of long term Levodopa therapy, remember dyskinesia is a side effect?

These were kind of tricky! And it has been over a year since I learned this material. :)

I looked up #1 and I think it's B now. GABA analogs increase GABA availablity which has anti-convulsant effect on the brain.

Hi Mixy,

Thanks for your response. I am still hunting for the answer and for #1, I am wondering if "a" is correct. This is because, under carbamazepine it states, "it has the ability to inhibit polysynaptic responses and to block sodium channels to prevent the formation of repetitive action potentials in the abnormal focus".

Now, that does look a tricky question! I hope you all don't mind my going back and forth discussing this.

Regarding carbamazepine, I know it works by stabilizing sodium channels by delaying the channels from recovering too soon. I don't recall anything regarding calcium channels. I looked in my pharm book and it only mentions the NA+ channels also. Carbamazepine works similiarly like phenytoin, which also works with NA+ channels.

Both of your answers contain CA2+ in them, so I am not sure. Was there originally an answer with only NA+ channels?

1. would be (b)- i do know that carbamazepine blocks na+ channels and increases gaba activity.

2. would be (b)- r/t gingival hyperplasia

3. decreased rigidity.

levodopa treats stiffness, tremors, spasms.

muscle twitching would be an adverse effect of levodopa, belonging to the subset of dyskinesias.

leslie

PsychNurseWannaBe,

Thanks and no there was no answer with only Na channels. That's what is confusing me.