Neostigmine

A to Z Drug Facts

Neostigmine

	Action
	Indications
	Contraindications
	Route/Dosage
	Interactions
	Lab Test Interferences
	Adverse Reactions
	Precautions
Patient Care Considerations
	Administration/Storage
	Assessment/Interventions
	Patient/Family Education

(nee-oh-STIGG-meen)

Prostigmin

Class: Cholinergic muscle stimulant/Anticholinesterase

Action Facilitates myoneural junction impulse transmission by inhibiting acetylcholine destruction by cholinesterase.

Indications Neostigmine bromide (oral) and methylsulfate (injection): Diagnosis of myasthenia gravis; symptomatic control of myasthenia gravis; antidote for nondepolarizing neuromuscular blocking agents after surgery. Neostigmine methylsulfate: Prevention and treatment of postoperative distention and urinary retention.

Contraindications Hypersensitivity to anticholinesterases and bromides; mechanical intestinal or urinary obstruction; peritonitis.

Route/Dosage

Diagnosis of Myasthenia gravis

ADULTS: IM 0.022 mg/kg. CHILDREN: IM 0.04 mg/kg.

Control of Myasthenia Gravis

ADULTS: PO 15 to 375 mg/day; SC/IM 1 mL of 1:2000 solution (0.5 mg); individualize subsequent doses. CHILDREN: IM/IV/SC 0.01 to 0.04 mg/kg dose q 2 to 3 hr prn.

Antidote

ADULTS: IV 0.5 to 2 mg by slow infusion repeated as needed, preceded by 0.6 to 1.2 mg of atropine sulfate. May be repeated prn up to total dose of 5 mg. CHILDREN: IV 0.07 to 0.08 mg/kg/dose preceded by 0.008 to 0.025 mg/kg/dose atropine sulfate.

Prevention of Postoperative Urinary Distention and Retention

ADULTS: SC/IM 1 mL of 1:4000 solution (0.25 mg) after surgery; repeat q 4 to 6 hr for 2 or 3 days.

Treatment of Postoperative Distention

ADULTS: SC/IM 1 mL of 1:2000 solution (0.5 mg), as required.

Treatment of Urinary Retention

ADULTS: SC/IM 1 mL of 1:2000 solution (0.5 mg) after bladder is emptied; continue 0.5 mg injection every 3 h for at least 5 injections.

Interactions

Corticosteroids: May antagonize anticholinesterases in myasthenia gravis, producing profound muscular depression. Succinylcholine: Neuromuscular blockade produced by succinylcholine may be either prolonged or antagonized.

Lab Test Interferences None well documented.

Adverse Reactions

CV: Arrhythmia (bradycardia; tachycardia; atrioventricular block; nodal rhythm); nonspecific ECG changes; cardiac arrest; hypotension; syncope. CNS: Convulsions; dysarthria; dysphonia; dizziness; loss of consciousness; drowsiness; headache. DERM: Rash; urticaria; flushing. EENT: Lacrimation; miosis; spasm of accommodation; diplopia; conjunctival hyperemia; visual changes. GI: Increased salivary, gastric and intestinal secretions; nausea; vomiting; dysphagia; increased peristalsis; diarrhea; abdominal cramps; flatulence. GU: Urinary urgency; frequency and incontinence. RESP: Increased tracheobronchial secretions; laryngospasm; bronchiolar constriction; respiratory paralysis; dyspnea; respiratory depression; respiratory arrest; bronchospasm. OTHER: Allergy and anaphylaxis; weakness; fasciculations; muscle cramps and spasms; arthralgia; diaphoresis.

Precautions

Pregnancy: Category C. Lactation: Undetermined. Children: Safety and efficacy in urinary tract indications not established. Special-risk patients: Use with caution in patients with epilepsy, bronchial asthma, bradycardia, recent coronary occlusion, vagotonia, hyperthyroidism, cardiac arrhythmias or peptic ulcer. Anticholinesterase insensitivity: May develop. Hypersensitivity: Anaphylaxis may occur. Have atropine and antishock meds available.

PATIENT CARE CONSIDERATIONS

Administration/Storage

Give with food or milk to reduce adverse effects. Tablet is poorly absorbed via GI tract and requires considerably larger dose than parenteral form.
If administering IV, push at rate of 0.5 mg/min.
Store tablets in tightly-closed containers.
Protect injectable product from light.

Assessment/Interventions

Obtain patient history, including drug history and any known allergies.
Obtain baseline assessment of pulse rate, respiratory rate, blood pressure.
Provide oxygen and oxygen delivery system set-up at bedside.
Continuously reassess for respiratory depression.
Ensure availability of atropine to prevent or reduce adverse effects. When administering atropine and neostigmine, use separate syringes.
If used for urinary retention, consult with physician to catheterize patient if no effects noted after 1 hr of administration.
Notify physician if heart rate is < 80/min. Atropine may be needed to restore heart rate.
If patient becomes hypotensive, place in supine position until BP has stabilized.

OVERDOSAGE: SIGNS & SYMPTOMS
	Abdominal cramps, miosis, diarrhea, sweating, excessive salivation, panic attacks, progressive muscle weakness leading to paralysis and death, urinary urgency, anxiety

Patient/Family Education

Identify potential adverse effects and tell patient to inform physician if any occur. Tell patient to report time effects occur, length of time since last dose, and type of adverse effects.
Explain that long-term use may induce drug tolerance and dosage adjustment may be necessary.
When drug is used for myasthenia gravis, advise patient to keep diary to record time at which muscle weakness and other symptoms occur. This log will enable dosage adjustment. Timing of dose is very important and schedule must be adhered to.