Neostigmine bromide
Neostigmine bromide (Prostigmin Bromide)
Neostigmine
(nee-oh- STIG-meen)
Pregnancy Category: C Prostigmin Bromide (Rx)
Neostigmine methylsulfate
Neostigmine methylsulfate (Prostigmin Injection)
Neostigmine
(nee-oh- STIG-meen)
Pregnancy Category: C Prostigmin Injection PMS-Neostigmine Methylsulfate (Rx)

Classification: Indirectly acting cholinergic-acetylcholinesterase inhibitor

Action/Kinetics: Acetylcholinesterase inhibitor that causes an increase in the concentration of acetylcholine at the myoneural junction, thus facilitating transmission of impulses across the myoneural junction. In myasthenia gravis, muscle strength is increased. May also act on the autonomic ganglia of the CNS. Prevents or relieves postoperative distention by increasing gastric motility and tone and prevents or relieves urinary retention by increasing the tone of the detrusor muscle of the bladder. Shorter acting than ambenonium chloride and pyridostigmine. Atropine is often given concomitantly to control side effects. Onset: PO, 45-75 min; IM, 20-30 min; IV, 4-8 min. Time to peak effect, parenteral: 20-30 min. Duration: All routes, 2.5-4 hr. t 1/2, PO: 42-60 min; IM: 51-90 min; IV: 47-60 min. Eliminated through the urine (about 40% unchanged).

Uses: Diagnosis and treatment of myasthenia gravis. Prophylaxis and treatment of postoperative distention or urinary retention. Antidote for tubocurarine and other nondepolarizing drugs.

Contraindications: Hypersensitivity, mechanical obstruction of GI or urinary tract, peritonitis, history of bromide sensitivity. Vesical neck obstruction of urinary bladder. Lactation.

Special Concerns: Safety and effectiveness in children have not been established. Use with caution in clients with bronchial asthma, bradycardia, vagotonia, epilepsy, hyperthyroidism, peptic ulcer, cardiac arrhythmias, or recent coronary occlusion. May cause uterine irritability and premature labor if given IV to pregnant women near term. In geriatric clients, the duration of action may be increased.

Side Effects: GI: N&V;, diarrhea, abdominal cramps, involuntary defecation, salivation, dysphagia, flatulence, increased gastric and intestinal secretions. CV: Bradycardia, tachycardia, hypotension, ECG changes, nodal rhythm, cardiac arrest syncope, AV block substernal pain, thrombophlebitis after IV use. CNS: Headache, seizures malaise, weakness, dysarthria, dizziness, drowsiness, loss of consciousness. Respiratory: Increased oral, pharyngeal, and bronchial secretions; bronchospasms, skeletal muscle paralysis, laryngospasm, central respiratory paralysis, respiratory depression or arrest dyspnea. Ophthalmologic: Miosis, double vision, lacrimation, accommodation difficulties, hyperemia of conjunctiva, visual changes. Musculoskeletal: Muscle fasciculations or weakness, muscle cramps or spasms, arthralgia. Other: Skin rashes, urinary frequency and incontinence, sweating, flushing, allergic reactions, anaphylaxis, urticaria. These effects can usually be reversed by parenteral administration of 0.6 mg of atropine sulfate, which should be readily available.
Cholinergic crisis, due to overdosage, must be distinguished from myasthenic crisis (worsening of the disease), since cholinergic crisis involves removal of drug therapy, while myasthenic crisis involves an increase in anticholinesterase therapy.

Overdose Management: Symptoms: Abdominal cramps, vomiting, diarrhea, epigastric distress, excessive salivation, cold sweating, pallor, blurred vision, urinary urgency, fasciculation and paralysis of voluntary muscles (including the tongue) miosis, increased BP (may be accompanied by bradycardia), sensation of internal trembling, panic, severe anxiety. Treatment: Discontinue medication temporarily. Give atropine, 0.5-1 mg IV (up to 5-10 or more mg may be needed to get the HR to 80 beats/min). Supportive treatment including artificial respiration and oxygen.

Drug Interactions: Aminoglycosides / Neuromuscular blockade Atropine / Atropine suppresses symptoms of excess GI stimulation caused by cholinergic drugs Corticosteroids / Effect of neostigmine Magnesium salts / Antagonize the effects of anticholinesterases Mecamylamine / Intense hypotensive response Organophosphate-type insecticides/pesticides / Added systemic effects with cholinesterase inhibitors Succinylcholine / Neuromuscular blocking effects

How Supplied: Neostigmine bromide: Tablet: 15 mg. Neostigmine methylsulfate: Injection: 0.5 mg/mL, 1 mg/mL

Dosage
Neostigmine bromide ?Tablets Treat myasthenia gravis.
Adults: 15 mg q 3-4 hr; adjust dose and frequency as needed. Usual maintenance: 150 mg/day with dosing intervals determined by client response. Pediatric, 2 mg/kg (60 mg/m ²) daily in six to eight divided doses.
Neostigmine methylsulfate ?IM, IV, SC Diagnosis of myasthenia gravis.
Adults, IM, SC: 1.5 mg given with 0.6 mg atropine; pediatric, IM: 0.04 mg/kg (1 mg/m ²); or, IV: 0.02 mg/kg (0.5 mg/m ²).
Treat myasthenia gravis.
Adults, IM, SC: 0.5 mg. Pediatric, IM, SC: 0.01-0.04 mg/kg q 2-3 hr.
Antidote for tubocurarine.
Adults, IV: 0.5-2 mg slowly with 0.6-1.2 mg atropine sulfate. Can repeat if necessary up to total dose of 5 mg. Pediatric, IV: 0.04 mg/kg with 0.02 mg/kg atropine sulfate.
Prevention of postoperative GI distention or urinary retention.
Adults, IM, SC: 0.25 mg (1 mL of the 1:4,000 solution) immediately after surgery repeated q 4-6 hr for 2-3 days.
Treatment of postoperative GI distention.
Adults, IM, SC: 0.5 mg (1 mL of the 1:2,000 solution) as required.
Treatment of urinary retention.
Adults, IM, SC: 0.5 mg (1 mL of the 1:2,000 solution). If urination does not occur within 1 hr after 0.5 mg, the client should be catheterized. After the bladder is emptied, 0.5 mg is given q 3 hr for at least five injections.