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penicillin G sodium
generic
Adult Dosing .
Dosage forms: INJ
infections, bacterial
- [4 million units IM/IV q4h]
- Max: 30 million units/day; Alt: 12-30 million units/day IV divided q4-6h; Info: dose, duration vary by infection type, severity
neurosyphilis
- [18-24 million units/day IV via continuous infusion or divided q4h x10-14 days]
- Info: 1st-line agent
endocarditis
- [12-30 million units/day IV via continuous infusion or divided q4-6h x4-6wk]
- Info: dose, duration varies with infection severity, pathogen susceptibility, valve type, symptom duration; may give with aminoglycoside gram positive synergy; refer to AHA guidelines
anthrax, systemic
- [4 million units IV q4h for at least 2wk]
- Info: for penicillin-susceptible B. anthracis including cutaneous infection with systemic involvement; not 1st-line agent; part of multi-drug regimen; switch to PO antibiotic for post-exposure prophylaxis if inhalational exposure
pneumonia, community-acquired
- [2-4 million units IV q4-6h for at least 5 days]
- Info: for inpatient tx
Lyme disease (off-label)
- [18-24 million units/day IV divided q4h x14-21 days]
- Info: for neurologic disease; may switch to PO regimen when possible to complete course; not 1st-line agent; search 'Lyme' for epocrates Lyme Disease Diagnosis & Treatment decision tool
meningitis, bacterial (off-label)
- [4 million units IV q4h]
- Info: may be part of multi-drug regimen
renal dosing
- [see below]
- CrCl 10-50: give usual divided dose x1, then give 50% usual divided dose q4-5h; CrCl <10: give usual divided dose x1, then give 50% usual divided dose q8-10h; Info: consider further dose decr. if both renal and hepatic impairment
- HD: give usual divided dose x1, then decr. usual divided dose by 50-80%, on dialysis days administer after dialysis; consider supplement if next maintenance dose not due right after dialysis; PD: give usual divided dose x1, then decr. usual divided dose by 50-80%; no supplement; Info: consider further dose decr. if both renal and hepatic impairment
hepatic dosing
- [not defined]
Peds Dosing .
- Dosage forms: INJ
infections, bacterial
- [neonates]
- Dose: 50,000-100,000 units/kg/day IM/IV divided q6-12h; Info: for cellulitis, impetigo, erysipelas, septic arthritis, osteomyelitis; dose, duration vary by infection type, severity
- [infants/children]
- Dose: 100,000-400,000 units/kg/day IM/IV divided q4-6h; Info: for cellulitis, impetigo, erysipelas, septic arthritis, osteomyelitis; dose, duration vary by infection type, severity
meningitis
- [neonates]
- Dose: 100,000-200,000 units/kg/day IM/IV divided q6-12h
- [infants/children]
- Dose: 250,000-400,000 units/kg/day IM/IV divided q4-6h; Max: 24 million units/day
meningitis, Group B Strep
- [neonates]
- Dose: 250,000-450,000 units/kg/day IM/IV divided q8h
- [infants/children]
- Dose: 450,000 units/kg/day IM/IV divided q6h
syphilis, congenital
- [neonates]
- Dose: 100,000 units/kg/day IV divided q12h x1st 7 days of life, then 150,000 units/kg/day IV divided q8h to complete 10 days total; Info: repeat entire course if >1 day missed; 1st-line agent
- [infants/children]
- Dose: 50,000 units/kg/dose IV q4-6h x10 days; Info: 1st-line agent
neurosyphilis
- [adolescents]
- Dose: 18-24 million units/day IV via continuous infusion or divided q4h x10-14 days; Info: 1st-line agent
endocarditis
- [200,000-300,000 units/kg/day IV divided q4h for at least 4wk]
- Max: 12-24 million units/day; Info: dose, duration varies with pathogen susceptibility, valve type; may give with gentamicin gram positive synergy; refer to AHA guidelines
anthrax, systemic
- [neonates >32 wk gestation]
- Dose: 200,000-400,000 units/kg/day IV divided q6-12h for at least 2wk; Info: for penicillin-susceptible B. anthracis including cutaneous infection with systemic involvement; part of multi-drug regimen; dose, frequency depend on gestational and post-natal age; switch to PO antibiotic x60 days total if inhalational exposure
- [1 mo and older]
- Dose: 400,000 units/kg/day IV divided q4h for at least 2wk; Max: 4 million units/dose; Info: penicillin-susceptible B. anthracis including cutaneous infection with systemic involvement; part of multi-drug regimen; switch to PO antibiotic x60 days total if inhalational exposure
pneumonia, community-acquired
- [100,000-250,000 units/kg/day IV divided q4-6h x10 days]
- Info: refer to IDSA guidelines
Lyme disease (off-label)
- [200,000-400,000 units/kg/day IV divided q4h x14-21 days]
- Max: 18-24 million units/day; Info: for neurologic disease; may switch to PO regimen when possible to complete course; not 1st-line agent; search 'Lyme' for epocrates Lyme Disease Diagnosis & Treatment decision tool
renal dosing
- [see below]
- CrCl 10-50: give usual divided dose x1, then decr. usual divided dose by 25%; CrCl <10: give usual divided dose x1, then decr. usual divided dose by 50-80%; Info: consider further dose decr. if both renal and hepatic impairment
- HD: give usual divided dose x1, then decr. usual divided dose by 50-80%, on dialysis days administer after dialysis; consider supplement if next maintenance dose not due right after dialysis; PD: give usual divided dose x1, then decr. usual divided dose by 50-80%; no supplement; Info: consider further dose decr. if both renal and hepatic impairment
hepatic dosing
- [not defined]
Contraindications / Cautions .
- hypersensitivity to drug or ingredient
- caution: hypersensitivity to beta-lactams
- caution: asthma
- caution: asthma history
- caution: antibiotic-associated colitis history, recent
- caution: seizure disorder
- caution: renal impairment
- caution: sodium restriction
- caution: >10 million units/day dose
Drug Interactions .
Overview
penicillin G
penicillin
- OAT1 substrate
- OAT3 substrate
- alters GI flora
- antiplatelet effects
- bactericidal activity requires bacterial growth
- impairs immunomodulatory bacterial infective agent
- lowers seizure threshold
Avoid/Use Alternative
- aldesleukin
- amifampridine
- BCG live intravesical
- cholera vaccine, live
- enoxaparin
- fecal microbiota, live
- fondaparinux
- iohexol
- methotrexate
- typhoid vaccine, live
Monitor/Modify Tx
- abrocitinib
- acalabrutinib
- ado-trastuzumab emtansine
- afatinib
- alpha-tocopherol (vitamin E)
- alprostadil intracavernous
- alprostadil intravenous
- alteplase
- anacaulase topical
- anagrelide
- antithrombin
- apixaban
- argatroban
- asparaginase
- aspirin
- avapritinib
- axitinib
- bevacizumab
- binimetinib
- bivalirudin
- brentuximab vedotin
- bromelain
- bromfenac ophthalmic
- bupropion
- cabazitaxel
- cabozantinib
- calaspargase
- cangrelor
- caplacizumab
- carfilzomib
- celecoxib
- cilostazol
- citalopram
- clopidogrel
- collagenase clostridium histolyticum
- cysteamine
- dabigatran
- dalteparin
- danshen
- dasatinib
- deferasirox
- defibrotide
- desvenlafaxine
- deuruxolitinib
- diclofenac
- diclofenac ophthalmic
- diclofenac topical
- diflunisal
- dimethyl fumarate
- diosmin
- dipyridamole
- diroximel fumarate
- duloxetine
- edoxaban
- encorafenib
- epoprostenol
- eptifibatide
- erlotinib
- escitalopram
- ethanol (alcoholic beverage)
- etodolac
- evening primrose oil
- fenoprofen
- fenugreek
- fluoxetine
- flurbiprofen
- flurbiprofen ophthalmic
- fluvoxamine
- fruquintinib
- garlic
- gefitinib
- gemtuzumab ozogamicin
- ginkgo
- heparin
- hydrocortisone
- ibrutinib
- ibuprofen
- ibuprofen lysine
- icosapent ethyl
- imatinib
- indomethacin
- iopamidol
- ketoprofen
- ketorolac
- ketorolac ophthalmic
- lenvatinib
- levomilnacipran
- lifileucel
- magnesium salicylate
- meclofenamate
- mefenamic acid
- meloxicam
- methyl salicylate topical
- milnacipran
- mitotane
- monomethyl fumarate
- mycophenolate mofetil
- mycophenolic acid
- nabumetone
- naproxen
- nattokinase
- nepafenac ophthalmic
- niacin (vitamin B3)
- nilotinib
- nintedanib
- nusinersen
- obinutuzumab
- omega-3-acid
- oxaliplatin
- oxaprozin
- pacritinib
- paroxetine
- pazopanib
- pegaspargase
- pentosan polysulfate sodium
- pentoxifylline
- piperacillin
- piroxicam
- pirtobrutinib
- plasminogen, human
- ponatinib
- porfimer
- pralsetinib
- prasugrel
- ramucirumab
- ranibizumab
- regorafenib
- remibrutinib
- resveratrol
- reteplase
- revakinagene taroretcel
- rivaroxaban
- salsalate
- saw palmetto
- selpercatinib
- selumetinib
- sepiapterin
- sertraline
- sirolimus albumin-bound
- sorafenib
- sotatercept
- sulindac
- sunitinib
- temsirolimus
- tenecteplase
- ticagrelor
- tipranavir
- tirofiban
- tisotumab vedotin
- tivozanib
- tolmetin
- tovorafenib
- trametinib
- trazodone
- treosulfan
- treprostinil
- upadacitinib
- vadadustat
- valproic acid
- vandetanib
- venlafaxine
- vilazodone
- vinpocetine
- vorapaxar
- vortioxetine
- warfarin
- willow bark
- zanubrutinib
- ziv-aflibercept
Therapeutic Advantage
- amikacin
- gentamicin
- probenecid
- streptomycin
- tobramycin
Caution Advised
- acetazolamide
- brivaracetam
- busulfan
- cannabidiol
- carbamazepine
- cenobamate
- chlorambucil
- clobazam
- clomipramine
- clonazepam
- clorazepate
- clozapine
- demeclocycline
- diazepam
- doxycycline
- eravacycline
- eslicarbazepine acetate
- ethosuximide
- felbamate
- fenfluramine
- fosphenytoin
- gabapentin
- ganaxolone
- hydroxychloroquine
- lacosamide
- lactulose
- lamotrigine
- levetiracetam
- lorazepam
- magnesium citrate
- methsuximide
- midazolam
- minocycline
- oxcarbazepine
- perampanel
- phenobarbital
- phenytoin
- polyethylene glycol
- polyethylene glycol/electrolytes
- pregabalin
- primidone
- promethazine
- rufinamide
- sarecycline
- sodium benzoate
- sodium phenylacetate
- sodium picosulfate
- stiripentol
- sulfate bowel prep
- tetracycline
- tiagabine
- topiramate
- tramadol
- vigabatrin
- zonisamide
Adverse Reactions .
Serious Reactions
- anaphylaxis
- hypersensitivity reaction, immediate or delayed
- serum sickness-like reaction
- cutaneous reaction, severe
- exfoliative dermatitis
- Stevens-Johnson syndrome
- drug reaction with eosinophilia and systemic symptoms
- toxic epidermal necrolysis
- acute generalized exanthematous pustulosis
- superinfection
- C. difficile-associated diarrhea
- hemolytic anemia
- neutropenia
- interstitial nephritis
- renal tubular necrosis
- electrolyte imbalance (high-dose use)
- hyperkalemia (high-dose use with potassium salt form)
- neurotoxicity (high-dose use)
- bleeding (high-dose use)
Common Reactions
- nausea
- vomiting
- diarrhea
- urticaria
- pruritus
- fever
- rash
- injection site pain
- thrombophlebitis
- stomatitis
- black hairy tongue
Safety/Monitoring .
Monitoring Parameters
Cr at baseline, then if prolonged high-dose tx continue frequently; CBC, electrolytes, LFTs, cardiac/vascular status frequently if prolonged high-dose tx
Look/Sound-Alike Drug Names
penicillin G sodium confused with: ampicillin
Pregnancy/Lactation .
Pregnancy
Clinical Summary
may use during pregnancy; drug of choice for neurosyphilis during pregnancy; no known risk of fetal harm based on human data
Lactation
Clinical Summary
may use while breastfeeding; no known risk of infant harm, though possible risk of infant diarrhea, rash, urticaria, thrush, and somnolence based on limited human data; no human data available to assess effects on milk production
Pharmacology .
Metabolism: for penicillin: liver; CYP450: unknown
Excretion: for penicillin: urine 58-85%; Half-life: 31-50min
Subclass: Anthrax ; Beta-Lactams ; Penicillins, Natural
Mechanism of Action
for penicillin: binds to peptidoglycan, inhibiting cell wall synthesis
Formulary .
No Formulary Selected
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