Geocillin, a semisynthetic penicillin, is the sodium salt of the indanyl
ester of Geopen (carbenicillin disodium ). The chemical name is: 1-(5-Indanyl)-N-(2-carboxy-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]
hept-6-yl)-2-phenylmalonamate monosodium salt.
The empirical formula is: C26H25N2NaO6S
and molecular weight is 516.55.
Geocillin tablets are yellow, capsule-shaped and film-coated, made of
a white crystalline solid. Carbenicillin is freely soluble in water. Each
Geocillin tablet contains 382 mg of carbenicillin, 118 mg of indanyl sodium
ester. Each Geocillin tablet contains 23 mg of sodium.
Inert ingredients are: glycine; magnesium stearate and sodium
lauryl sulfate. May also include the following: hydroxypropyl cellulose;
hydroxypropyl methylcellulose; opaspray (which may include Blue 2 Lake,
Yellow 6 Lake, Yellow 10 Lake, and other inert ingredients), opadry light
yellow (which may contain D&C Yellow 10 Lake, FD&C Yellow 6 Lake and other
inert ingredients); opadry clear (which may contain other inert ingredients).