Canadian Pharmacists Journal - May/June 2019 - CPH6

Provincial Differences in Drug Interchangeability

Interchangeability

Drug	interchangeability	is	determined	by	the	individual	
province	or	territory.	Pharmacists	may	be	legally	required	
to	dispense	an	interchangeable	generic	product	where	
they	exist.	In	addition,	hospital	formularies	often	restrict	
medication	product	selection	to	one	formulation	that	
may	not	necessarily	reflect	the	choices	available	in	the	
community.11

Province

For	provinces	where	there	is	mandatory	interchangeability,	
these	provinces	require	that	the	interchangeable	product	
dispensed	be	the	lowest	priced	product	available.	A	patient	
may	still	choose	to	pay	the	difference	between	the	brand	
name	and	alternative	formulation.	In	provinces	with	optional	
interchangeability,	pharmacists	may	substitute	a	prescribed	
drug	with	an	interchangeable	drug,	but	it	is	not	mandatory.24
Again	the	patient	should	be	informed	and	have	the	option	to	
pay	the	difference	in	price	if	they	prefer.25-36

Québec

Mandatory

Optional

Manitoba
Newfoundland &
Labrador
Ontario
PEI
Saskatchewan
Alberta
British Columbia
New Brunswick
Nova Scotia
Mandatory vs. optional interchangeability is not a legal
obligation, but rather deals with reimbursement issues.

There	are	exceptions	to	these	rules	in	some	provinces.	For	example,	in	Québec,	the	innovator	formulation	of	
cyclosporine	is	listed	in	Appendix	V	of	the	List of Medications	for	which	the	lowest	price	method	does	not	apply	and	
therefore	can	not	be	substituted.37	In	Ontario,	the	innovator	formulation	of	cyclosporine	is	provided	free	of	charge	to	the	
patient	under	the	Special	Drugs	Program	when	dispensed	by	a	specially	designated	facility	(i.e.,	transplant	centre	hospital	
pharmacy).	

Considerations for Switching
Product	monographs	for	critical	dose	immunosuppressant	drugs	all	provide	cautions	on	switching	between	formulations,	
including	informing	physicians	responsible	for	maintenance	therapy	in	order	to	initiate	therapeutic	drug	monitoring	to	
achieve	target	concentrations	in	individual	patients.6-9
The	Canadian	Society	of	Transplantation	has	also	provided	a	number	of	recommendations	on	generic	
immunosuppression	in	solid	organ	transplant	recipients	based	on	available	clinical	research.11

Canadian Society of Transplantation Recommendations on Generic Immunosuppression in
Transplant Recipients
Generic immunosuppression use should be approached with caution.
The intended drug product formulation should be explicitly stated on all prescriptions.
*	Consistency	of	drug	products	in	the	immunosuppressive	regimen	should	be	maintained	
*	Switching	formulations	and	the	use	of	more	than	one	preparation	in	the	same	patient	should	be	avoided
Close monitoring is essential when initiating therapy and with any change in drug product.
Because	of	known	differences	in	pharmacokinetics	and	insufficient	data,	the routine use of generic
immunosuppressive formulations in pediatric transplant recipients is not recommended.
Patient education regarding generic medications and generic substitution is essential.
More extensive data should be made available regarding	the	efficacy	and	safety	of	generic	immunosuppressive	
therapy	for	proper	use	and	monitoring.
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Canadian Pharmacists Journal - May/June 2019

Table of Contents for the Digital Edition of Canadian Pharmacists Journal - May/June 2019
