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Crexont
carbidopa/ levodopa
Adult Dosing .
Dosage forms: ER CAP: 35 mg/140 mg, 52.5 mg/210 mg, 70 mg/280 mg, 87.5 mg/350 mg
Special Note
- [formulation clarification]
- Info: carbidopa/levodopa ER cap not interchangeable w/ ER tab; do not substitute on a mg to mg basis; may interchange w/ other ER cap at approx. mg to mg basis
parkinsonism
- [levodopa-naive pts]
- Dose: individualize dose PO bid; Start: 35 mg/140 mg PO bid x3 days; Max: 525 mg/2100 mg per day; Info: titrate dose to optimal effect; dosing frequency may be incr. up to qid if needed; use lowest effective dose; do not open cap; taper dose gradually to D/C
- [conversion from IR levodopa <500 mg/day, most frequent single-dose 100 mg]
- Dose: individualize dose PO bid; Start: 70 mg/280 mg PO bid x1-3 days; Max: 525 mg/2100 mg per day; Info: titrate dose to optimal effect; dosing frequency may be incr. up to qid if needed; use lowest effective dose; do not open cap; taper dose gradually to D/C
- [conversion from IR levodopa <500 mg/day, most frequent single-dose 150 mg]
- Dose: individualize dose PO bid; Start: 105 mg/420 mg PO bid x1-3 days; Max: 525 mg/2100 mg per day; Info: titrate dose to optimal effect; dosing frequency may be incr. up to qid if needed; use lowest effective dose; do not open cap; taper dose gradually to D/C
- [conversion from IR levodopa <500 mg/day, most frequent single-dose 200 mg]
- Dose: individualize dose PO bid; Start: 140 mg/560 mg PO bid x1-3 days; Max: 525 mg/2100 mg per day; Info: titrate dose to optimal effect; dosing frequency may be incr. up to qid if needed; use lowest effective dose; do not open cap; taper dose gradually to D/C
- [conversion from IR levodopa >500 mg/day, most frequent single-dose 100 mg]
- Dose: individualize dose PO tid; Start: 70 mg/280 mg PO tid x1-3 days; Max: 525 mg/2100 mg per day; Info: titrate dose to optimal effect; dosing frequency may be incr. up to qid if needed; use lowest effective dose; do not open cap; taper dose gradually to D/C
- [conversion from IR levodopa >500 mg/day, most frequent single-dose 150 mg]
- Dose: individualize dose PO tid; Start: 105 mg/420 mg PO tid x1-3 days; Max: 525 mg/2100 mg per day; Info: titrate dose to optimal effect; dosing frequency may be incr. up to qid if needed; use lowest effective dose; do not open cap; taper dose gradually to D/C
- [conversion from IR levodopa >500 mg/day, most frequent single-dose 200 mg]
- Dose: individualize dose PO tid; Start: 140 mg/560 mg PO tid x1-3 days; Max: 525 mg/2100 mg per day; Info: titrate dose to optimal effect; dosing frequency may be incr. up to qid if needed; use lowest effective dose; do not open cap; taper dose gradually to D/C
- [conversion from IR levodopa >500 mg/day, most frequent single-dose >200 mg]
- Dose: individualize dose PO tid; Start: 175 mg/700 mg PO tid x1-3 days; Max: 525 mg/2100 mg per day; Info: titrate dose to optimal effect; dosing frequency may be incr. up to qid if needed; use lowest effective dose; do not open cap; taper dose gradually to D/C
renal dosing
- [not defined]
- renal impairment: not defined
- HD/PD: not defined
hepatic dosing
- [not defined]
Peds Dosing .
Peds dosing is currently unavailable or not applicable for this drug.
Contraindications / Cautions .
- hypersensitivity to drug or ingredient
- non-selective MAO inhibitor use w/in 14 days
- psychotic disorder, major
- glaucoma, angle-closure
- abrupt withdrawal
- avoid: alcohol use
- caution: CNS depressant use, concurrent
- caution: diet, high-protein
- caution: hepatic impairment
- caution: renal impairment
- caution: sleep disorder
- caution: dyskinesia
- caution: cardiovascular dz, severe
- caution: arrhythmia w/ MI hx
- caution: pulmonary dz, severe
- caution: asthma
- caution: endocrine dz
- caution: PUD
- caution: GI bleeding hx
- caution: glaucoma, open-angle
Drug Interactions .
Overview
carbidopa
dopa-decarboxylase inhibitor
- binds to polyvalent cations
- dopa-decarboxylase inhibitor
levodopa
dopamine precursor
- affected by altered gastrointestinal motility
- affects growth hormone diagnostic test results
- binds to polyvalent cations
- CNS depression
- dopamine agonist
- gastric pH sensitive
- hypotensive effects
- add MAO inhibitor to Interaction Check if recent (14 days) use
Contraindicated
- isocarboxazid
- linezolid
- phenelzine
- selegiline transdermal
- tranylcypromine
- yohimbe
Avoid/Use Alternative
- aldesleukin
- amisulpride
- butalbital
- clonidine
- codeine
- doxylamine
- ethanol
- ethanol (in some formulations)
- foslevodopa
- hydrocodone
- isoniazid
- kava
- kratom
- lofexidine
- macimorelin
- metaxalone
- metoclopramide
- midazolam
- oxybate
- procarbazine
- promethazine
- ropeginterferon alfa-2b
- thalidomide
- trimethobenzamide
- zuranolone
Monitor/Modify Tx
- acebutolol
- alfentanil
- alfuzosin
- aliskiren
- alprazolam
- amantadine
- amifostine
- amiloride
- amitriptyline
- amlodipine
- amoxapine
- apomorphine
- apraclonidine ophthalmic
- aprocitentan
- aripiprazole bimonthly injection
- aripiprazole lauroxil
- aripiprazole monthly injection
- aripiprazole oral
- articaine
- asenapine
- atenolol
- avanafil
- azilsartan medoxomil
- baclofen intrathecal
- benazepril
- berberine
- betaxolol
- betaxolol ophthalmic
- bethanechol
- bexagliflozin
- bisoprolol
- bortezomib
- brexpiprazole
- brimonidine ophthalmic
- brimonidine topical
- bromocriptine
- bumetanide
- bupivacaine
- bupivacaine liposomal
- buprenorphine
- butorphanol
- cabergoline
- canagliflozin
- candesartan cilexetil
- cannabis
- captopril
- carbamazepine
- cariprazine
- carteolol ophthalmic
- carvedilol
- chlordiazepoxide
- chloroprocaine
- chlorothiazide
- chlorpromazine
- chlorthalidone
- cilostazol
- clevidipine
- clobazam
- clofarabine
- clomipramine
- clonazepam
- clorazepate
- clozapine
- coenzyme Q-10
- dapagliflozin
- daridorexant
- denileukin diftitox
- desflurane
- desipramine
- dexmedetomidine
- dexmedetomidine injection
- diazepam
- dihydrocodeine
- diltiazem
- dinutuximab
- dipyridamole
- doxazosin
- doxepin
- dronabinol
- droperidol
- droxidopa
- duloxetine
- empagliflozin
- enalapril
- enalaprilat
- entacapone
- entrectinib
- eplerenone
- epoprostenol
- ertugliflozin
- esketamine
- esmolol
- estazolam
- eszopiclone
- ethacrynic acid
- etomidate
- felodipine
- fenoldopam
- fentanyl
- ferric citrate
- ferric maltol
- ferrous fumarate
- ferrous gluconate
- ferrous sulfate
- ferumoxytol
- flaxseed
- flibanserin
- fluphenazine
- flurazepam
- fosinopril
- furosemide
- gabapentin
- gabapentin enacarbil
- garlic
- gilteritinib
- guanfacine
- haloperidol
- hydralazine
- hydrochlorothiazide
- hydromorphone
- hydroxyzine
- ifosfamide
- iloperidone
- iloprost
- iloprost inhaled
- imipramine
- indapamide
- irbesartan
- iron sucrose
- isoflurane
- isosorbide dinitrate
- isosorbide mononitrate
- isradipine
- ketamine
- labetalol
- landiolol
- lemborexant
- levobunolol ophthalmic
- levorphanol
- lidocaine
- lisinopril
- lorazepam
- losartan
- loxapine
- lubiprostone
- lumateperone
- lurasidone
- magnesium sulfate
- maraviroc
- meperidine
- mepivacaine
- methadone
- methohexital
- methyldopa
- methylene blue injection
- metolazone
- metoprolol
- milrinone
- minoxidil
- mirtazapine
- moexipril
- molindone
- morphine
- nadolol
- nalbuphine
- nattokinase
- naxitamab
- nebivolol
- nelarabine
- nicardipine
- nifedipine
- nimodipine
- nisoldipine
- nitric oxide
- nitrite
- nitroglycerin
- nitroprusside
- nortriptyline
- olanzapine
- oliceridine
- olmesartan medoxomil
- opicapone
- opium
- oxazepam
- oxybutynin
- oxycodone
- oxymorphone
- paliperidone
- palopegteriparatide
- pentamidine
- pentazocine
- pentobarbital
- perindopril
- perphenazine
- phenobarbital
- phenoxybenzamine
- phentolamine
- pindolol
- pramipexole
- prazosin
- pregabalin
- primidone
- prochlorperazine
- propafenone
- propofol
- propranolol
- protriptyline
- quazepam
- quetiapine
- quinapril
- ramipril
- rasagiline
- remifentanil
- remimazolam
- riociguat
- risperidone
- ropinirole
- ropivacaine
- rotigotine transdermal
- sacubitril
- safinamide
- sapropterin
- selegiline
- sevoflurane
- sildenafil
- silodosin
- sodium ferric gluconate complex
- sotagliflozin
- sotalol
- sparsentan
- spironolactone
- sucroferric oxyhydroxide
- sufentanil
- suvorexant
- tadalafil
- tagraxofusp
- tamsulosin
- tapentadol
- taurine
- telmisartan
- temazepam
- terazosin
- thioridazine
- thiothixene
- timolol
- timolol ophthalmic
- tizanidine
- tolcapone
- torsemide
- tramadol
- trandolapril
- trazodone
- treprostinil
- triamterene
- triazolam
- trifluoperazine
- trihexyphenidyl
- trimipramine
- valsartan
- vardenafil
- verapamil
- vosoritide
- zaleplon
- ziconotide
- ziprasidone
- zolpidem
Caution Advised
- 5-HTP
- allopurinol
- almotriptan
- baclofen
- brivaracetam
- brompheniramine
- bupropion
- buspirone
- cannabidiol
- carbinoxamine
- carisoprodol
- cenobamate
- cetirizine
- chamomile, German
- chlophedianol
- chlorpheniramine
- chlorzoxazone
- citalopram
- clemastine
- cyclobenzaprine
- cyproheptadine
- dantrolene
- darifenacin
- desvenlafaxine
- deutetrabenazine
- dexbrompheniramine
- dexchlorpheniramine
- dexlansoprazole
- dichlorphenamide
- difelikefalin
- difenoxin
- dimenhydrinate
- diphenhydramine
- diphenoxylate
- domperidone
- doxepin topical
- efavirenz
- eletriptan
- escitalopram
- eslicarbazepine acetate
- esomeprazole
- ethosuximide
- felbamate
- fenfluramine
- fesoterodine
- fluoxetine
- fluvoxamine
- fosphenytoin
- frovatriptan
- ganaxolone
- glofitamab
- glycopyrrolate
- hyoscyamine
- lacosamide
- lamotrigine
- lansoprazole
- lasmiditan
- levetiracetam
- levocetirizine
- levomilnacipran
- meclizine
- melatonin
- meprobamate
- methocarbamol
- methsuximide
- metyrapone
- metyrosine
- milnacipran
- mitotane
- mosunetuzumab
- mycophenolate mofetil
- naltrexone
- naratriptan
- nefazodone
- omeprazole
- orphenadrine
- oxcarbazepine
- pantoprazole
- paroxetine
- passion flower
- perampanel
- pheniramine
- phenytoin
- pimozide
- pyrilamine
- rabeprazole
- ramelteon
- repotrectinib
- rizatriptan
- rufinamide
- scopolamine
- selinexor
- sertraline
- solifenacin
- stiripentol
- sumatriptan
- tasimelteon
- tetrabenazine
- thiotepa
- tiagabine
- tolterodine
- topiramate
- triprolidine
- trospium
- valbenazine
- valerian
- valproic acid
- venlafaxine
- vigabatrin
- vilazodone
- viloxazine
- vonoprazan
- zolmitriptan
- zonisamide
Adverse Reactions .
Serious Reactions
- dyskinesia
- bradykinesia
- hypotension, orthostatic
- syncope
- MI
- arrhythmia
- sudden sleep episodes
- depression
- suicidal ideation
- suicide attempt
- hallucinations
- psychosis
- GI bleeding
- blood dyscrasias
- hypersensitivity rxn
- NMS-like sx if abrupt D/C
Common Reactions
- nausea
- dizziness
- headache
- dyskinesia
- insomnia
- abnormal dreams
- xerostomia
- anxiety
- constipation
- vomiting
- hypotension, orthostatic
- hallucinations
- confusion
- UTI
- depression
- body fluid discoloration, dark
- mood changes
- compulsive behaviors
Safety/Monitoring .
Monitoring Parameters
BUN/Cr, CBC, LFTs if extended tx; IOP if glaucoma; cardiac fxn if extended tx or during initial inpatient dose adjustment then periodically thereafter if arrhythmias w/ MI hx
Look/Sound-Alike Drug Names
levodopa/carbidopa confused with: carbidopa
Pregnancy/Lactation .
Pregnancy
Clinical Summary
weigh risk/benefit during pregnancy; risk of teratogenicity not expected based on limited human data; possible risk of teratogenicity based on conflicting animal data at greater than MRHD
Lactation
Clinical Summary
carbidopa: weigh risk/benefit while breastfeeding; inadequate human data available to assess risk of infant harm; no human data available to assess effects on milk production
levodopa: weigh risk/benefit while breastfeeding; no known risk of infant harm based on limited human data; inadequate human data available, though theoretical decr. milk production based on decr. prolactin levels
Pharmacology .
Metabolism: for carbidopa: unknown; CYP450: unknown; for levodopa: decarboxylation, O-methylation; CYP450: unknown; Info: active metabolite (dopamine)
Excretion: for carbidopa: urine primarily (30% unchanged); Half-life: 2h; for levodopa: urine; Half-life: 2h; Info: half-life may be prolonged due to continuous absorption
Subclass: Dystonias/Parkinson Disease
Mechanism of Action
carbidopa inhibits peripheral levodopa decarboxylation; levodopa crosses blood-brain barrier and serves as dopamine precursor
Formulary .
No Formulary Selected
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