Mosby's 2014 Nursing Drug Reference (256 page)

Canada only   Side effects:
italics
= common;
bold
= life-threatening   
Nurse Alert

memantine (Rx)

(me-man′teen)

Ebixa
, Namenda, Namenda XR

Func. class.:
Anti-Alzheimer agent

Chem. class.:
NMDA receptor antagonist

ACTION:

Antagonist action of CNS NMDA receptors that may contribute to the symptoms of Alzheimer’s disease

USES:

Moderate to severe dementia in Alzheimer’s disease

Unlabeled uses:
Vascular dementia, acquired pendular nystagmus

CONTRAINDICATIONS:

Children, hypersensitivity

Precautions:
Pregnancy (B), breastfeeding, renal disease, GU conditions that raise urine pH, seizures, severe hepatic disease, renal failure

DOSAGE AND ROUTES
Calculator

• Adult:
PO
5 mg/day, may increase dose in 5-mg increments ≥1 wk intervals; recommended target dose of 20 mg/day as 10 mg bid; × R 7 mg q day increase in 7 mg increments ≥ q wk to 28 mg/day

Available forms:
Tabs 5, 10 mg; tab titration pak 5, 10 mg; oral sol 2 mg/ml (10 mg/5 ml); cap ext rel 7, 14, 21, 28 mg

Administer:

• 
Can be taken without regard to meals

• 
Twice a day if dose >5 mg

• 
Dosage adjusted to response no more than q1wk

• 
Ext rel caps:
do not crush, chew, divide; swallow whole or open and sprinkle on applesauce

• 
Oral sol
using device provided; remove dosing syringe, green cap, plastic tube from plastic; attach tube to green cap; open cap by pushing down on cap, turning counterclockwise; remove unscrewed cap; carefully remove seal from bottle, discard; insert plastic tube fully into bottle, screw green cap tightly onto bottle by turning cap clockwise; keeping bottle upright on table, remove lid; with plunger fully depressed, insert tip of syringe into cap; while holding syringe, gently pull up on plunger; remove syringe; invert syringe, slowly press plunger to level that removes large air bubbles; keep plunger in inverted position; few small air bubbles may be present

SIDE EFFECTS

CNS:
Dizziness, confusion
, somnolence, headache, hallucinations,
stroke

CV:
Hypertension,
heart failure, CHF

GI:
Vomiting, constipation

HEMA:
Anemia

INTEG:
Rash

MISC:
Back pain, fatigue, pain

RESP:
Coughing, dyspnea

PHARMACOKINETICS

Rapidly absorbed PO, 44% protein binding, very little metabolism, 57%-82% excreted unchanged in urine, terminal elimination half-life 60-80 hr

INTERACTIONS

• 
May alter levels of both products: hydrochlorothiazide, triamterene, cimetidine, quiNIDine, ranitidine, nicotine

Increase:
effect—levodopa, some ergots

Decrease:
clearance of memantine—products that make urine alkaline (sodium bicarbonate, carbonic anhydrase inhibitors)

NURSING CONSIDERATIONS
Assess:

• 
Alzheimer’s dementia:
affect, mood, behavioral changes; hallucinations, confusion, attention, orientation, memory

Perform/provide:

• 
Assistance with ambulation during beginning therapy; dizziness may occur

Evaluate:

• 
Therapeutic response: decrease in confusion, improved mood, maintenance of function, even with no improvement in symptoms

Teach patient/family:

• 
To report side effects: restlessness, psychosis, visual hallucinations, stupor, LOC; may indicate overdose

• 
To use product exactly as prescribed; that product not a cure, to avoid alcohol, nicotine

• 
To use oral sol dispenser

• 
To avoid OTC, herbal products unless approved by prescriber

Canada only   Side effects:
italics
= common;
bold
= life-threatening   
Nurse Alert

HIGH ALERT
meperidine (Rx)

(me-per′i-deen)

Demerol, Meperitab

Func. class.:
Opioid analgesic

Chem. class.:
Phenylpiperidine derivative

 

Controlled Substance Schedule II

Do not confuse:
meperidine
/HYDROmorphone/meprobamate/morphine
Demerol
/Dilaudid/Desyrel/Demulen

ACTION:

Depresses pain impulse transmission at the spinal cord level by interacting with opioid receptors

USES:

Moderate to severe pain preoperatively, postoperatively

Unlabeled uses:
Obstetric/regional analgesic, acute severe headache/migraine, shaking chills induced by IV amphotericin B or postoperative shivering

CONTRAINDICATIONS:

Hypersensitivity, severe respiratory insufficiency

Precautions:
Pregnancy (C), breastfeeding, children <18 yr, geriatric patients, addictive personality, increased intracranial pressure, MI (acute), severe heart disease, respiratory depression, renal/hepatic disease, seizure disorder, abrupt discontinuation, chronic pain

DOSAGE AND ROUTES
Calculator
Moderate to severe pain

• Adult:
PO/SUBCUT/IM
50-150 mg q3-4hr prn;
CONT INF
15-35 mg/hr as
PCA
10 mg then 1- to 5-mg incremental dose; lockout interval 6-10 min

• Child:
PO/SUBCUT/IM
1-1.8 mg/kg q3-4hr prn, max 100 mg q4hr

Labor analgesia

• Adult:
SUBCUT/IM
50-100 mg given when contractions regularly spaced, repeat q1-3hr prn

Preoperatively

• Adult:
IM/SUBCUT
50-100 mg 30-90 min before surgery

• Child:
IM/SUBCUT
1-2.2 mg/kg 30-90 min before surgery, max 100 mg

Renal dose

• 
Avoid or modify dose

Available forms:
Inj 10, 25, 50, 75, 100 mg/ml; tabs 50, 100 mg; oral sol 50 mg/5 ml

Administer:
PO route

• 
May give with food or milk to decrease GI irritation

• 
Oral liquid:
dilute in 4 oz water

IM/SUBCUT route

• 
Patient should remain recumbent for 1 hr after IM/SUBCUT route

• 
With antiemetic for nausea, vomiting

• 
When pain beginning to return; determine dosage interval by patient response

• 
In gradually decreasing dose after long-term use; withdrawal symptoms may occur

• 
Inject IM into large muscle mass; IM preferred route for multiple inj

Direct IV route

• 
Dilute to conc of 10 mg/ml with sterile water for inj or NS

• 
Inject slowly ≤25 mg/min

• 
Have emergency equipment and opiate antagonist on hand

Continuous IV INF route

• 
Dilute to conc of 1 mg/ml

• 
Infuse using inf pump

Syringe compatibilities:
Butorphanol, chlorproMAZINE, cimetidine, dimenhyDRINATE, diphenhydrAMINE, droperidol, fentaNYL, glycopyrrolate, hydrOXYzine, ketamine, metoclopramide, midazolam, pentazocine, perphenazine, prochlorperazine, promazine, promethazine, ranitidine, scopolamine

Y-site compatibilities:
Amifostine, amikacin, atenolol, aztreonam, bumetanide, ceFAZolin, cefotaxime, cefOXitin, cefTAZidime, ceftizoxime, cefTRIAXone, cefuroxime, cephapirin, cisatracurium, cladribine, clindamycin, diltiazem, diphenhydrAMINE, DOBUTamine, DOPamine, DOXOrubicin HCL, doxycycline, droperidol, erythromycin, famotidine, filgrastim, fluconazole, fludarabine, gallium, gentamicin, granisetron, hydrocortisone, insulin (regular), kanamycin, labetalol, lidocaine, methyldopate, melphalan, metoclopramide, metoprolol, metroNIDAZOLE, moxalactam, ondansetron, oxacillin, oxytocin, PACLitaxel, penicillin G potassium, piperacillin, potassium chloride, propofol, propranolol, ranitidine, remifentanil, sargramostim, teniposide, thiotepa, ticarcillin, ticarcillin/clavulanate, tobramycin, vancomycin, verapamil, vinorelbine

Continuous intrathecal INF route

• 
Use controlled inf device; implantable controlled micro inf device used for highly concentrated inf, monitor for several days after implantation

• 
Filling of inf reservoir should only be done by those fully qualified

• 
To prevent pain, depletion of reservoir should be avoided

SIDE EFFECTS

CNS:
Drowsiness, dizziness, confusion, headache, sedation, euphoria
,
increased intracranial pressure, seizures,
serotonin syndrome

CV:
Palpitations, bradycardia, hypotension, change in B/P, tachycardia (IV)

EENT:
Tinnitus, blurred vision, miosis, diplopia, depressed corneal reflex

GI:
Nausea, vomiting, anorexia, constipation, cramps, biliary spasm, paralytic ileus

GU:
Urinary retention, dysuria

INTEG:
Rash, urticaria, bruising, flushing, diaphoresis, pruritus

RESP:
Respiratory depression

SYST:
Anaphylaxis

PHARMACOKINETICS

Metabolized by liver (to active/inactive metabolites), excreted by kidneys; crosses placenta, excreted in breast milk; half-life 3-4 hr; toxic by-product accumulation can result from regular use or renal disease; protein binding 65%-75%

PO:
Onset 15 min, peak 1/2-1 hr, duration 2-4 hr, absorption 50%

SUBCUT/IM:
Onset 10 min, peak 1/2-1 hr, duration 2-4 hr, well absorbed

IV:
Onset 5 min, duration 2 hr

INTERACTIONS

 
May cause fatal reaction: MAOIs, procarbazine

Increase:
serotonin syndrome, neuroleptic malignant syndrome, SSRIs, SNRIs, serotonin-receptor agonists

Increase:
effects with other CNS depressants, alcohol, opioids, sedative/hypnotics, antipsychotics, skeletal muscle relaxants

Increase:
adverse reactions—protease inhibitor antiretrovirals

Decrease:
meperidine effect—phenytoin

Drug/Herb

Increase:
CNS depression—St. John’s wort

Drug/Lab Test

Increase:
amylase, lipase

NURSING CONSIDERATIONS
Assess:

• 
Pain:
location, type, character; give product before pain becomes extreme; reassess after 60 min (IM, SUBCUT, PO) and 5-10 min (IV)

• 
Renal function prior to initiating therapy; poor renal function can lead to ac
cumulation of toxic metabolite and seizures

• 
I&O ratio; check for decreasing output; may indicate urinary retention

• 
For constipation; increase fluids, bulk in diet; give stimulant laxatives if needed

• 
CNS changes: dizziness, drowsiness, hallucinations, euphoria, LOC, pupil reactions with chronic or high-dose use

• 
Allergic reactions: rash, urticaria

 
Respiratory dysfunction:
depression, character, rate, rhythm; notify prescriber if respirations are <12/min

• 
CNS stimulation: with chronic or high doses

Perform/provide:

• 
Storage in light-resistant container at room temp

Evaluate:

• 
Therapeutic response: decrease in pain

Teach patient/family:

• 
To report any symptoms of CNS changes, allergic reactions

• 
That physical dependency may result from extended use, use should be short term only

• 
That drowsiness, dizziness may occur

• 
That withdrawal symptoms may occur: nausea, vomiting, cramps, fever, faintness, anorexia

• 
To make position changes slowly; orthostatic hypotension can occur

• 
To avoid OTC medications, alcohol unless directed by prescriber

TREATMENT OF OVERDOSE:

Naloxone (Narcan) 0.2-0.8 mg IV, caution in physically dependent patients, O
2
, IV fluids, vasopressors

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