Details About Overdose or Poisoning Generic Salt :: Methocarbamol
Drug Pharmacology ::
I. Pharmacology. Methocarbamolis a centrally acting muscle relaxant. It does not directly relaxskeletal muscle and does not depress neuromuscular transmission ormuscle excitability; muscle relaxation is probably related to itssedative effects. After intravenous administration, the onset of actionis nearly immediate. Elimination occurs by hepatic metabolism, with aserum half-life of 0.9–2.2 hours.
Drug Indications ::
Controlof painful muscle spasm caused by black widow spider envenomation (seeSpiders). Methocarbamol should be used as an adjunct to othermedications (eg, morphine, diazepam) that are considered more effective.
Management of muscle spasm caused by mild tetanus (see Tetanus) or strychnine (see Strychnine) poisoning.
Drug Contra-Indications ::
Known hypersensitivity to the drug.
History of epilepsy (intravenous methocarbamol may precipitate seizures).
Drug Adverse Effects ::
IV. Adverse effects
Dizziness, drowsiness, nausea, flushing, and metallic taste may occur.
Extravasation from an intravenous site may cause phlebitis and sloughing. Do not administer subcutaneously.
Hypotension,bradycardia, and syncope have occurred after intramuscular orintravenous administration. Keep the patient in a recumbent positionfor 10–15 minutes after injection.
Urticaria and anaphylactic reactions have been reported.
E. Use in pregnancy. There is no reported experience, and no FDA category has been assigned.
Drug Lab Interactions ::
Drug or laboratory interactions
Methocarbamol produces additive sedation with alcohol and other CNS depressants.
Methocarbamol may cause false-positive urine 5-hydroxyindole acetic acid (5-HIAA) and vanillylmandelic acid (VMA) results.
The urine may turn brown, black, or blue after it stands.
Drug Dose Management ::
Dosage and method of administration
1. Administer1 g (children, 15 mg/kg) IV over 5 minutes, followed by 0.5 g in 250 mLof 5% dextrose (children, 10 mg/kg in 5 mL of 5% dextrose) over 4hours. Repeat every 6 hours to a maximum of 3 g daily.
2. Fortetanus, higher doses are usually recommended. Give 1–2 g IV initially,no faster than 300 mg/min; if needed, use a continuous infusion up to atotal of 3 g.
3. Theusual intramuscular dose is 500 mg every 8 hours for adults and 10mg/kg every 8 hours for children. Do not inject more than 5 mL into thegluteal region. Do not give subcutaneously.
Oral. Switchto oral administration as soon as tolerated. Give 0.5–1 g (children,10–15 mg/kg) PO or by gastric tube every 6 hours. The maximum dose is1.5 g every 6 hours; for tetanus, the maximum adult dose is 24 g/day.
Drug Chemical Formulations ::
Parenteral. Methocarbamol (Robaxin, others), 100 mg/mL in 10-mL vials.
Oral. Methocarbamol (Robaxin, others), 500- and 750-mg tablets.
The suggested minimum stocking level to treat a 70-kg adult for the first 24 hours is 24 vials (100 mg/mL, 10 mL each).