Synthroid vs generic: are they the same? — for Canada
Synthroid is the originator brand for the active ingredient Levothyroxine. Once the original patent expired, authorised generic versions of the same active ingredient became available. For most users at 25mcg, 50mcg, 75mcg, 100mcg, 150mcg, the practical question is: is the generic just as good, and what really differs?
Canada context
Authorised generics of Levothyroxine are typically dispensed in Canada alongside or instead of branded Synthroid. Canadian pharmacies (Shoppers Drug Mart, Rexall, London Drugs and many independents) are licensed provincially, and pharmacists in several provinces can prescribe for minor ailments. The pharmacist applies local equivalence rules at the point of dispensing; the brand vs generic price gap in CAD is usually the most decisive economic factor for ongoing use.
- Regulator
- Health Canada
- Currency
- CAD
What is the same
Authorised generics of Levothyroxine contain the same active substance at the same 25mcg, 50mcg, 75mcg, 100mcg, 150mcg strength as Synthroid, with regulator-required bioequivalence to the originator. Clinical effect is, on average, the same. According to the prescribing information, generics meet the same regulatory standard and can substitute for the brand in most patients.
What can differ
Differences include manufacturer, country of production, excipients, tablet appearance, packaging and price. A small minority of patients react to a specific excipient that varies between manufacturers. Price is usually significantly lower for generics — often the most decisive practical difference for chronic use.
Frequently asked questions
Is generic Levothyroxine as effective as Synthroid? ▾
For most users at 25mcg, 50mcg, 75mcg, 100mcg, 150mcg, yes — authorised generics of Levothyroxine are required to demonstrate bioequivalence to Synthroid and produce the same clinical effect on average. Some users notice no difference; a few report subjective differences that are usually due to excipients or expectation.
Why does Synthroid cost more than the generic? ▾
The price difference reflects the originator's development costs, brand recognition and marketing, plus the larger volume and competition among generic manufacturers. The active ingredient Levothyroxine itself is identical between brand and authorised generic at 25mcg, 50mcg, 75mcg, 100mcg, 150mcg.
Synthroid vs generic: are they the same? in other countries
- the United StatesFDA (Food and Drug Administration)
- the United KingdomMHRA (Medicines and Healthcare products Regulatory Agency)
- SpainAEMPS (Agencia Española de Medicamentos y Productos Sanitarios)
- MexicoCOFEPRIS (Comisión Federal para la Protección contra Riesgos Sanitarios)
- ArgentinaANMAT (Administración Nacional de Medicamentos, Alimentos y Tecnología Médica)
- GermanyBfArM (Bundesinstitut für Arzneimittel und Medizinprodukte)
- FranceANSM (Agence nationale de sécurité du médicament et des produits de santé)
- ItalyAIFA (Agenzia Italiana del Farmaco)
- BrazilANVISA (Agência Nacional de Vigilância Sanitária)
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.