Parkinson's Disease Medications PDF

69 I PARKINSON DISEASE DOPAMINE REPLACEMENT DRUGS & AGONISTS DRUG DOSING SAFETY/SIDE EFFECTS/MONITORING Carbidopa/levodopa: levodopa is a precursor of dopamine. Carbidopa inhibits dopa decarboxylase enzyme, preventing peripheral metabolism of levodopa. Carbldopa/Levodopa Slnemet, Sinemet CR'...

69 I PARKINSON DISEASE DOPAMINE REPLACEMENT DRUGS & AGONISTS DRUG DOSING SAFETY/SIDE EFFECTS/MONITORING Carbidopa/levodopa: levodopa is a precursor of dopamine. Carbidopa inhibits dopa decarboxylase enzyme, preventing peripheral metabolism of levodopa. Carbldopa/Levodopa Slnemet, Sinemet CR' Tablets Rytary ER capsule Duopa Enteral suspension given via J-tube lnbrija Levodopa capsule for oral inhaler, used as needed for symptoms during off periods IR (starting dose): 25/100 mg POTID CR (starting dose): 50/200 mg POBID CR tab can be cut in half do not crush or chew Rytary: start at 23.75/95 mg PO TID if levodopa-naive; take whole or sprinkle on a small amount of applesauce /nbrija: 84 mg (2 capsules) inhaled up to 5 times daily as needed, max dose: 420 mg/day Titrate cautiously CONTRAINDICATIONS Non-selective MAO inhibitors within 14 days, narrow angle glaucoma SIDE EFFECTS Nausea, dizziness, orthostasis. dyskines!as, hallucinations, psychosis, xerostomia (dry mouth), dystonias (occasional, painful), confusion Can cause brown, black or dark discoloring of urine, saliva or sweat and can discolor clothing; positive Coombs test: discontinue dr~emolysis risk}: unusual sexual urges, priapism; i uric acid Rytary: suicidal ideation and attempts Duopa: GI complications NOTES 70-100 mg/day of carbidopa required to inhibit dopa decarboxylase Long-term use can lead to fluctuations in response and dyskinesias Separate from oral iron and high protein foods Do not dlscontlm1e abruptly; must be tapered Duopa cassettes: store in freezer, thaw in refrigerator prior to dispensing (good for I 12 weeks upon refrigeration) COMT inhibitors: increase the duration of action of levodopa; inhibit the enzyme catechol-0-methyltransferase (COMT) to prevent peripheral conversion of levodopa. COMT inhibitors should only be used with levodopa. Entacapone (Comtan) + carbidopa/levodopa (Stalevo) 200 mg PO with each dose of carbidopa/levodopa (max= 1,600 mg/day) Stalevo: carbidopa/levodopa in a ratio of 1:4 with 200 mg of entacapone in each tablet (example: 12.5/50/200 mg) Opicapone (Ongentys) SIDE EFFECTS Similar to levodopa, due to extending its duration NOTES J, in levodopa dose of 10-30% is usually necessary when adding on a COMT inhibitor Dyskinesias can occur earlier with COMT inhibitors 50 mg POQHS Dose J, needed in liver disease Tolcapone (Tasmar) Rarely used due to hepatotoxicity risk Dopamine agonists: act similar to dopamine at the dopamine receptor. Pramlpexole (Mlrapex, MlrapexER} IR formulation also approved for restless legs syndrome (RLS) IR: start with 0.125 mg PO TID, titrate weekly to max of 1.5 mgTID WARNINGS Somnolence (including sudden daytime sleep attacks), orthostasis, hallucinations, dyskinesias, impulse control disorders ER: start with 0.375 mg PO daily, titrate weekly to max of 4.5 mg daily Rotigotine patch: application site (skin) reactions J, dose if CrCI < 50 mUmin (90% renally excreted) SIDE EFFECTS Dizziness, nausea, vomiting, dry mouth, peripheral edema, constipation Pramipexole: postural deformity (e.g., bent spine, dropped head), rhabdomyolysis Rotigotine: hyperhidrosis Roplnirole (Requlp XL, Requip') IR formulation also approved for RLS Rotigotine (Neupro) Patch Also approved for RLS IR: start with 0.25 mg PO Tl D, titrate weekly to max of 8 mg TID XL: start with 2 mg PO daily, titrate weekly to max of 24 mg daily Patch: start with 2 mg/24 hrs (early PD) Max dose: 8 mg/24 hours NOTES A slow titration (no more than weekly) is required due to orthostasis, dizziness, sleepiness; do not discontinue abruptly Ropinirole: CYP450 1A2 substrate; caution with CYP1A2 inhibitors I Bromocriptine is another drug in the class; no longer recommended Patch Apply once daily at the same time each day to the stomach, thigh, hip, side of the body, shoulder or upper arm; do not use the same site for at least 14 days Remove the patch before an MRI; do not apply a heat source over the patch; avoid if sensitivity/allergy to sulfites 886 ---------- -- --- -------------------------------- - - 'Brand discontinued but name still used in practice.