Table 7

The relative contributions of various metabolic pathways of galantamine in rats, dogs, and humans after single oral administration of [³H]galantamine hydrobromide at 2.5 mg base-Eq/kg body weight (animals) and 4 mg base-Eq (humans)

Group	Primary Metabolic Pathway	Metabolites	Rats		Dogs	Humans
Group	Primary Metabolic Pathway	Metabolites	Male	Female	Dogs	Poor metabolizers	Extensive metabolizers
I	Unchanged drug (UD)	UD	21.5	44.9	47.3	39.1	24.4
II	Oxidation/reduction	13, 14, 22, (17^7-150, 21^7-150)^7-a	4.6 (8.2)	5.3 (5.4)	1.6 (1.6)	3.5 (6.2)	— (0.2)
III	N-Oxidation	10, 17^7-150	7.8	2.9	2.7	19.2	8.8
IV	N-Demethylation	8, 16^7-150	10.8	7.4	19.8	7.0	4.5
V	O-Demethylation	6, 2^7-150, 3^7-150, 20^7-150, 21^7-150, 23^7-150	22.7	11.4	1.3	5.2	33.1
VI	Sulfate conjugation	15, (22^7-150, 23^7-150)^7-a	1.3 (1.3)	16.7 (17.3)	— (—)	— (0.4)	— (8.9)
VII	Glucuronidation	5, (2^7-150, 3^7-150)^7-a	4.1 (16.9)	4.5 (13.6)	14.7 (14.7)	13.4 (13.4)	10.2 (31.2)
		TOTAL^7-a	72.8	93.1	87.4	87.4	81.0

The figures represent the percentage of the administered dose and were derived from the mass balance of galantamine and its metabolites in urine and faeces. The metabolites have been assigned to one or another group on the basis of their primary metabolic pathway.

↵7-150 Secondary metabolite (derived from a primary metabolite).
↵7-a Metabolites in parentheses have not been included in the numerical total for that group to avoid double counting. The totals for these pathways are, however, included in parentheses.