Penicillin

Penicillin
[[File:|250px]] Chemical structure of penicillin V (representative)
Formula	C16H18N2O5S (penicillin V)
Administration	Oral, intravenous, intramuscular
Solubility	Varies by salt (potassium salt freely soluble in water)
Legal status	Prescription only
Brand names	Veetids, Pen-Vee K, V-Cillin K (penicillin V); Pfizerpen, Bicillin L-A (penicillin G)
Bioavailability	60–73% (penicillin V oral); ~30% (penicillin G oral); nearly 100% (IV/IM)
Recommended dose	250–500 mg every 6 hours (oral penicillin V); 1.2–24 million units/day (IV/IM penicillin G, depending on infection)
Upper limit	No strict upper limit in severe infections (doses up to 60 million units/day IV have been used under medical supervision)
LD50	>5000 mg/kg (rat, oral, penicillin V); >2000 mg/kg (various penicillins)