Can Phentermine cause acid reflux? 

Can Phentermine cause acid reflux? 

No, Phentermine does not generally cause acid reflux. This is not listed as a side effect of this medication and was not reported in any of the clinical trials. However, people always respond differently to medications. 

Some people may find Phentermine generally heavy on their stomach and some may experience mild heartburn. If you’re struggling with acid reflux, make sure you rule other factors out. 

Even if Phentermine is the one causing this side effect, it’s not bound to stay. Most side effects begin to subside as your body adjusts to the medication. Phentermine is generally recommended to take on an empty stomach and GI side effects are not commonly reported. (1)

Meanwhile, you can try OTC acid reducers like Omeprazole for a few weeks or as long as your acid reflux stays. If your symptoms are severe and are affecting the quality of your life, reach out to your healthcare provider. 

What factors can contribute to acid reflux while taking Phentermine?

While acid reflux is not a commonly reported side effect of Phentermine, there are some factors that could potentially contribute to its occurrence. One possible factor is the relaxation of the lower oesophagal sphincter (LES), a muscular ring that separates the stomach from the oesophagus. (2,3)

When the LES is relaxed, stomach acid can flow back into the oesophagus, leading to acid reflux. So make sure you talk to your healthcare provider and rule it out. 

Certain lifestyle habits and behaviours, such as consuming acidic or spicy foods, eating large meals, lying down after eating, or smoking, can also increase the likelihood of acid reflux.

Additionally, individual factors such as a history of gastrointestinal issues or a predisposition to acid reflux may make some individuals more susceptible to experiencing acid reflux while taking Phentermine.

It’s important to note that if you are experiencing persistent or severe acid reflux symptoms, it is advisable to consult with your healthcare provider.

Best tips to manage acid reflux while taking Phentermine

To manage acid reflux while taking Phentermine, there are several strategies you can try:

  • Avoid trigger foods: Identify and avoid foods and beverages that tend to trigger or worsen your acid reflux symptoms. These may include spicy foods, citrus fruits, chocolate, caffeine, alcohol, and fatty or fried foods (4).
  • Eat smaller, more frequent meals: Instead of large meals, try eating smaller portions throughout the day to reduce the pressure on your stomach and minimize acid reflux.
  • Don’t lie down immediately after eating: Wait at least two to three hours after a meal before lying down or going to bed. This allows your food to digest properly and reduces the chances of acid reflux. 
  • Maintain a healthy weight: Excess weight can put pressure on your abdomen, which can contribute to acid reflux. 
  • Quit smoking: Smoking can weaken the lower oesophagal sphincter and increase acid reflux symptoms. Quitting smoking can provide numerous health benefits, including a reduction in acid reflux symptoms.
  • Consider over-the-counter medications: Antacids or acid reducers (H2 blockers or proton pump inhibitors) may provide temporary relief from acid reflux symptoms. However, it is advisable to consult with a healthcare professional before starting any medication.

If you are experiencing persistent or severe acid reflux, it’s important to consult your healthcare provider. They may recommend additional medications or adjustments to your treatment plan to help manage your symptoms effectively.

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