Minor
Atorvastatin × Levothyroxine sodium
HMG-CoA reductase inhibitors (statins)×Thyroid hormones
Mechanism
Hypothyroidism itself raises LDL. Restoring euthyroid status on levothyroxine reduces statin need. No direct pharmacokinetic interaction.
Symptoms
The combination usually causes no specific symptoms. Each drug's individual side effects remain.
Management
On starting levothyroxine in patients on stable atorvastatin, check lipids 6–8 weeks after TSH normalises. If LDL drops below target, atorvastatin can be reduced. In newly diagnosed hypothyroidism with hypercholesterolaemia, delay statin start until euthyroid status is achieved.
Sources
- Lexicomp: Lexicomp Drug Interactions (2024)– Wolters Kluwer Clinical Drug Information, Inc. Lexi-Interact Online, 2024
- Pharmaceutical Press: Stockley's Drug Interactions, 12th edition (2024)– Preston CL (ed.). Stockley's Drug Interactions. 12th ed. London: Pharmaceutical Press; 2024