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magnesium oxide
generic
Adult Dosing .
Dosage forms: CAP: 250 mg, 400 mg, 500 mg; TAB: 241.3 mg, 250 mg, 253 mg, 500 mg
Special Note
- [strength clarification]
- Info: MgO contains approximately 60.325% elemental Mg; 400 mg MgO = 241.3 mg (19.86 mEq) elemental Mg; doses expressed as elemental Mg
dyspepsia
- [241.3 mg PO bid prn]
- Max: 482.6 mg/24h
dietary supplementation
- [individualize dose]
- Info: see Dietary Reference Intakes, Magnesium table
hypomagnesemia (off-label)
- [mild]
- Dose: 240-1000 mg/day PO divided qd-qid; Info: give smaller, more frequent doses to incr. absorption; adjust dose based on serum Mg levels
- [moderate-severe]
- Dose: 800-1600 mg/day PO divided bid-qid; Info: give smaller, more frequent doses to incr. absorption; adjust dose based on serum Mg levels
renal dosing
- [adjust dose amount]
- renal impairment: decr. usual dose, amount not defined
- HD: decr. usual dose, amount not defined; supplement after dialysis not defined; PD: decr. usual dose, amount not defined; supplement not defined
hepatic dosing
- [not defined]
Peds Dosing .
- Dosage forms: CAP: 250 mg, 400 mg, 500 mg; TAB: 241.3 mg, 250 mg, 253 mg, 500 mg
Special Note
- [strength clarification]
- Info: MgO contains approximately 60.325% elemental Mg; 400 mg MgO = 241.3 mg (19.86 mEq) elemental Mg; doses expressed as elemental Mg
dietary supplementation
- [individualize dose]
- Info: see Dietary Reference Intakes, Magnesium table
renal dosing
- [adjust dose amount]
- renal impairment: decr. usual dose, amount not defined
- HD: decr. usual dose, amount not defined; supplement after dialysis not defined; PD: decr. usual dose, amount not defined; supplement not defined
hepatic dosing
- [not defined]
Contraindications / Cautions .
- hypersensitivity to drug or ingredient
- colostomy
- ileostomy
- ulcerative colitis
- diverticulitis
- caution: renal impairment
- caution: botulism
Drug Interactions .
Overview
magnesium oxide
magnesium salt (antacid)
- gastric pH modulator
- polyvalent cation
Avoid/Use Alternative
- amphetamine
- calcitriol
- dextroamphetamine
- doxercalciferol
- mefenamic acid
- mesalamine
- methamphetamine
- methylphenidate
- nirogacestat
- potassium acid phosphate
- potassium phosphate
- quinine
- raltegravir
- selpercatinib
- sodium acid phosphate
- sodium phosphate (supplement)
- sotorasib
- trientine
- ziftomenib
Monitor/Modify Tx
- alendronate
- atazanavir
- azithromycin
- baloxavir marboxil
- bictegravir
- bisacodyl
- bosutinib
- cabotegravir
- captopril
- cefaclor
- cefdinir
- cefpodoxime
- cefuroxime axetil
- chloroquine
- ciprofloxacin
- cysteamine
- dasatinib
- defactinib
- deferiprone
- delafloxacin
- demeclocycline
- dicyclomine
- diflunisal
- digoxin
- dolutegravir
- domperidone
- doxycycline
- eltrombopag
- elvitegravir
- erlotinib
- ethambutol
- fexofenadine
- fosinopril
- gabapentin
- gefitinib
- glipizide
- hyoscyamine
- ibandronate
- itraconazole
- ketoconazole
- ledipasvir
- levofloxacin
- levoketoconazole
- levothyroxine
- methscopolamine
- mexiletine
- minocycline
- moxifloxacin
- mycophenolate mofetil
- mycophenolic acid
- naproxen
- neratinib
- nilotinib
- octreotide
- ofloxacin
- omadacycline
- pazopanib
- penicillamine
- pexidartinib
- phenytoin
- rifampin
- rilpivirine
- rilzabrutinib
- riociguat
- risedronate
- rosuvastatin
- sarecycline
- sotalol
- sparsentan
- taletrectinib
- tetracycline
- thyroid
- tipranavir
- triazolam
- vadadustat
- velpatasvir
Caution Advised
- belumosudil
- ferrous fumarate
- ferrous gluconate
- ferrous sulfate
- fosamprenavir
- lactulose
- peppermint
- sodium polystyrene sulfonate
Adverse Reactions .
Serious Reactions
may occur but none reported
Common Reactions
- diarrhea
- GI irritation
- weakness
- nausea
- vomiting
Safety/Monitoring .
Monitoring Parameters
Cr at baseline; electrolytes if Mg >50 mEq/day and renal impairment
Look/Sound-Alike Drug Names
magnesium oxide confused with: Megace
Pregnancy/Lactation .
Pregnancy
Clinical Summary
may use during pregnancy; recommended dietary allowance of elemental Mg 400 mg/day for pregnant patients 14-18 yo, 350 mg/day for pregnant patients 19-30 yo, and 360 mg/day for pregnant patients 31 yo and older; risk of fetal harm not expected based on limited human data
Lactation
Clinical Summary
may use while breastfeeding; no known risk of infant harm based on limited human data with other magnesium salts; inadequate human data available to assess effects on milk production
Formulary .
No Formulary Selected
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