phenytoin

RENAISSANCE RN · Jun 28, 2006

dilantin is a very basic drug ph 12.5. I believe it can only be mixed with ns.

your country may have different preparations for the drug. Here is a link http://www.rxlist.com. It indicates that a bolus is prepared and premixed with ns.

you can also check any iv med book..

good luck

christen13 · Jun 28, 2006

You are correct...phenytoin may only be pushed with NS...you will get a precipate....trust me on this one, I learned the hard way :)

In addition, it can be given as a slow inital bolus but is called phosphenytion (not sure about the spelling) via IV piggyback, once that is in you can push dilantion (once again, in NS only)

We give this to pretty much all of our head injuries, to prevent seizure.......in my experice it has always worked.

christen h

gods · Jun 29, 2006

Thanks guys for your help and thanks for the website adress. Any suggestions on IV med books, would be greatfull thanks.

regards Gods

JillyT · Jun 30, 2006

I really like this IV med book. It also comes in a PDA version.

http://www.us.elsevierhealth.com/product.jsp?isbn=9780323045520

dfk, RN, CRNA · Jul 3, 2006

i've given dilantin ivp thru a saline maintenance line.. slowly to avoid hypotension.. and yes.. only ns... use a filter (to be safe).. some literature says no filter.. but i would always use one..

and to christen, it hasn't been proven that giving dilantin to head injuries (without previous hx of sz) will actually have a benefit.. just my cents worth -

christen13 · Jul 4, 2006

thanks for the info on dilantin. We give it to ALL patients with a head injury....I have never seen a pt a seizure...but is this because it's working or they never needed it?? Guess we will never know...

christen

gradcare, LPN · Aug 8, 2006

Just watch the rate of infusing 50 mg/min is our unit recomendation. It is not just hypotension you have to watch out for, if I remember correctly dilantin was originally used as a cardiac rate controler (Na channel blocker) and if given too fast can result in bradycardias I have seen someone push dilantin too fast resulting in a brady arrest. Pt survived and had a substernal mass detected on the subsiquent chest CT (mass was felt sliding under the sternum on chest compressions)

dfk, RN, CRNA · Aug 8, 2006

Just watch the rate of infusing 50 mg/min is our unit recomendation. It is not just hypotension you have to watch out for, if I remember correctly dilantin was originally used as a cardiac rate controler (Na channel blocker) and if given too fast can result in bradycardias I have seen someone push dilantin too fast resulting in a brady arrest. Pt survived and had a substernal mass detected on the subsiquent chest CT (mass was felt sliding under the sternum on chest compressions)

interesting... thanks for the new!

gradcare, LPN · Aug 8, 2006

Yeah the rate reduction thing I have seen several times including a tachy that was not responding to the metoprolol took her down from 110 to 80 BPM. THe old cardiac usage was handed down to me by one of our more senior members of staff s looooong time ago. Don't know whether they were pulling my leg or not, with this person it's hard to tell. (Dry sense of humor great poker face)

Maybe an old school cardiac nurse can verify?

BAndersonRN · Aug 9, 2006

I've also heard that Dilantin was used at one time to treat tachyarrhythmias since it slows the influx through the Na+ channels. Because Dilantin (phenytoin) does have the ability to cause cardiac depression it should be given no faster than 40-50mg/min IV push, and as everyone else has mentioned it is only soluble in normal saline since it will precipitate in many other IV solutions. This is because Dilantin itself is highly insoluble and therefore must be mixed in propylene glycol (same chemical found in antifreeze) to improve the solublility of the IV form. Another drug that was mentioned earlier in the post was Cerebyx (fosphenytoin). This drug is actually a pro-drug of phenytoin, it is metabolized in the serum and converted to phenytoin (Dilantin) in the body. Fosphenytoin is much more soluble in solutions than phenytoin is and therefore does not need to be mixed in propylene glycol for IV administration. Cerebyx is dosed in PEs (or pheneytoin equivalents, ie. 50mg phenytoin= 50 PEs fosphenytoin). The benefit of using Cerebyx is that it doesn't have the same cardiac depressant properties as Dilantin so it can be given much more safely (and may be pushed faster too, up to 150mg(PEs)/min) to patients who may not be quite hemodynamically stable, the downfall is that Cerebyx is much more expensive than Dilantin (Cerebyx is about $80 per gram compared to Dilantin which is about $5 per gram). Seizure prophylaxis has been demonstrated to be effective by using either drug in patients sustaining a CHI/TBI, subdural hematoma (SDH), intracerebral hemorrhage (ICH), or subarachnoid hemorrhage (SAH) as long as it has been initiated early on in the course of treatment for the patient.

dfk, RN, CRNA · Aug 9, 2006

Seizure prophylaxis has been demonstrated to be effective by using either drug in patients sustaining a CHI/TBI, subdural hematoma (SDH), intracerebral hemorrhage (ICH), or subarachnoid hemorrhage (SAH) as long as it has been initiated early on in the course of treatment for the patient.

can you provide some direction to where you found this information? many neuro docs i've spoken with state that if no previous sz hx, there is no "definitive" clinical outcomes that it actually prevents sz. mostly used as a prophylaxis. thanks.