Does Aeterna Headache Medicine Stop Iron Absorption?
There is no evidence that acetaminophen (the likely active ingredient in Aeterna headache medicine) interferes with iron absorption. Acetaminophen is not among the medications documented to form complexes with iron or reduce iron bioavailability.
Medications That DO Interfere with Iron Absorption
The following medications have been demonstrated to significantly reduce iron absorption through chelation or complex formation when taken concurrently 1:
- Antibiotics: Tetracycline and derivatives (doxycycline, methacycline, oxytetracycline), ciprofloxacin 1
- Cardiovascular medications: Methyldopa, captopril 1
- Parkinson's medications: Levodopa, carbidopa 1
- Other medications: Penicillamine, thyroxine 1
Substances That Inhibit Iron Absorption
While acetaminophen does not affect iron absorption, other common substances do 2:
- Calcium-containing antacids: Calcium carbonate reduces plasma iron increase by 67% when taken simultaneously 3
- Sodium bicarbonate: Reduces plasma iron increase by 50% 3
- Tea and coffee: Polyphenols in these beverages inhibit iron absorption, though this effect can be overcome by consuming ascorbic acid or meat/fish/poultry with meals 2
- Plant components: Phytates in vegetables 2
Important Clinical Caveat
Aluminum hydroxide and magnesium hydroxide antacids do NOT significantly decrease iron absorption 3. Additionally, when calcium carbonate is present in a multivitamin tablet containing ascorbic acid, the competitive binding by ascorbic acid allows uninhibited iron absorption 3.
Practical Recommendation
Patients taking Aeterna or other acetaminophen-containing headache medications can take iron supplements at any time without concern for reduced absorption. However, if they are taking calcium-containing antacids or other medications listed above, iron should be taken at least 2 hours apart from these agents 1.