From the Guidelines
Doxycycline and antacids should be separated by at least 2 hours to minimize potential drug interactions.
Recommendations for Taking Doxycycline with Antacids
- Take doxycycline on a full stomach with a full glass of liquid to reduce gastrointestinal side effects, but avoid taking antacids or dairy products within 2 hours of doxycycline 1.
- Separate doxycycline dose by at least 2 hours from antacids that contain calcium, iron, magnesium, or sodium bicarbonate to prevent reduced absorption of doxycycline.
- Patients should take doxycycline exactly as individually prescribed, with doses not exceeding 200 mg per 24 hours, and taken as soon after sex as possible, but no later than 72 hours 1.
Gabapentin
There is no information provided in the given evidence regarding the use of gabapentin with antacids. However, in general clinical practice, it is recommended to take gabapentin with food to reduce gastrointestinal side effects, but there is no specific recommendation regarding the use of antacids.
From the FDA Drug Label
Absorption of tetracyclines is impaired by antacids containing aluminum, calcium, or magnesium, and iron-containing preparations. Gabapentin tablets can be taken with or without food. If you take an antacid containing aluminum and magnesium, such as Maalox®, Mylanta®, Gelusil®, Gaviscon®, or Di-Gel®, you should wait at least 2 hours before taking your next dose of gabapentin tablets.
Recommendations for taking antacids with doxycycline or gabapentin:
- Doxycycline: Antacids containing aluminum, calcium, or magnesium should be avoided as they impair the absorption of doxycycline.
- Gabapentin: If taking an antacid containing aluminum and magnesium, wait at least 2 hours before taking the next dose of gabapentin. 2 3
From the Research
Antacids and Doxycycline Interactions
- Doxycycline is a tetracycline derivative, and its absorption can be affected by antacids containing polyvalent cations such as aluminum, magnesium, and calcium 4.
- The interaction between doxycycline and antacids can result in a 50-90% reduction in doxycycline absorption 4.
- To minimize this interaction, it is recommended to take doxycycline and antacids at least 3 hours apart 4 or 4 hours before or 2 hours after administration of doxycycline 5.
Antacids and Gabapentin Interactions
- There is no direct evidence in the provided studies regarding the interaction between antacids and gabapentin.
- However, antacids can alter the gastric pH, which may affect the absorption of certain drugs, including gabapentin 6, 7, 5.
- The clinical significance of this potential interaction is unclear, and further studies are needed to determine the effects of antacids on gabapentin absorption.
General Recommendations
- Antacids can interact with various medications, including antibiotics, and reduce their absorption 8, 4, 5.
- To minimize potential interactions, it is recommended to take antacids and other medications at different times, such as 4 hours before or 2 hours after administration of the other medication 5.
- Patients should be aware of the potential interactions between antacids and their medications and consult their healthcare provider for guidance on taking these medications together 7, 5.