Lisinopril Does Not Contain Milk or Wheat
Lisinopril tablets contain neither milk (lactose) nor wheat-derived ingredients according to the FDA-approved formulation. The inactive ingredients listed in the official drug label are: calcium phosphate, magnesium stearate, mannitol, red iron oxide, and corn starch 1.
Key Formulation Facts
No lactose present: The FDA label explicitly lists all inactive ingredients, and lactose is not among them 1.
Corn starch only: The starch component comes from corn, not wheat 1. This is important for patients with celiac disease or wheat allergies, as corn starch is gluten-free 2.
Calcium phosphate as filler: Instead of lactose (which is commonly used in many medications), lisinopril uses calcium phosphate and mannitol as bulking agents 1.
Important Clinical Context
While lisinopril itself does not contain lactose, this is noteworthy because:
Lactose is extremely common in medications: Approximately 60-70% of medications contain lactose as an excipient 3, 4.
Many antihypertensives do contain lactose: Studies show high prevalence of dairy-derived excipients in various drug classes, though specific data on ACE inhibitors varies 3.
Generic substitutions may differ: While the reference formulation uses corn starch and calcium phosphate, patients should verify ingredients with their pharmacist when switching manufacturers, as inactive ingredients can vary between generic versions 2.
Practical Recommendations
Safe for lactose intolerance: Patients with lactose intolerance can safely take lisinopril without concern for lactose-related symptoms 1.
Safe for celiac disease: The corn starch used is gluten-free, making lisinopril appropriate for patients with celiac disease or gluten sensitivity 2.
Verify with pharmacist: When prescribing for patients with severe allergies or intolerances, add "verify gluten-free and lactose-free formulation" to the prescription to ensure the dispensed product meets these requirements 2.