Gastroenterology and Hepatobiliary Sciences

What Causes a Sour Taste in the Mouth? 5 Possible Reasons

admin Apr 23, 2025

When you want to enjoy the taste of coffee or tea in the early mornings, but when your mouth gives you a sour taste, you will feel unpleasant and irritated. Occasionally, the experience of a sour or bitter taste in mouth is common, which causes an unpleasant experience.

However, if this taste occurs frequently, it shouldn’t be ignored, as it may indicate health issues. The sour taste in the mouth can be caused by several factors. This blog explores reasons for a sour taste in the mouth, understands the potential causes and takes necessary steps to address the issue.

Reason for sour taste in the mouth

Acid reflux: One of the common causes of a sour taste in mouth is acid reflux. This condition occurs when stomach acid flows back up into the oesophagus, leading to a sour or bitter taste in mouth. Acid reflux is one of the common symptoms for individuals suffering from gastro-oesophageal reflux disease (GERD). In Individuals suffering from GERD, the lower oesophageal sphincter that prevents food from returning to the oesophagus opens abnormally, allowing stomach contents to flow back. This may cause a sour or bitter taste, which is a frequent symptom.

Oral infections: Poor oral hygiene can contribute to bacterial growth, which can cause a metallic taste or bitter taste in mouth. The overgrowth of bacteria can also lead to oral infections and gum disease that can change the oral environment, leading to a sour taste. Below are the possible oral conditions that can lead to a sour taste.

Dry mouth syndrome: This condition, also known as xerostomia, refers to inadequate production of saliva required for digestion. This insufficient amount can alter the taste of food and leave a bad taste in the mouth.

Oral candidiasis: The yeast infection in the mouth or throat is referred to as oral candidiasis, commonly found in people with weakened immune systems. It can cause white patches on the tongue and mouth, along with a sour taste.

Medications: Certain medications can cause a bitter or sour taste after eating as a side effect. This side effect may occur due to drug interactions with taste receptors in the brain or when the taste of medication mixes with saliva. Likewise, many different drugs are known to cause this issue. The common class of drugs that cause altered taste are.

Antibiotics
Chemotherapeutic drugs
Psychiatric drugs
Antihypertensive drugs
Neuro drugs

If you suspect that your medication is causing a sour taste in your mouth, talk to your healthcare provider about alternative options or strategies to mitigate this side effect.

Dehydration: Excessive dehydration can lead to various symptoms, including dry mouth and altered taste perception. When the body lacks an adequate amount of fluids, saliva production is impaired, leading to a sour taste in the mouth. To prevent dehydration and its associated symptoms, one has to drink plenty of water throughout the day. Avoid consuming excess dehydrating beverages like alcohol and caffeine.

Neurological conditions: Neurological conditions can interfere with the mechanism of how the brain interprets taste signals. These disorders can lead to dysgeusia, a distortion in the sense of taste, often resulting in sour or metallic flavours. In addition, infections from the sinus can cause post-nasal drip, causing persistent sour throat as mucous interacts with the taste buds.

Other possible reasons for a sour taste in the mouth apart from the mentioned causes include:

Pregnancy: Physiological and hormonal changes during pregnancy can cause a bitter or sour taste in the mouth.
Menopause: Women who are reaching or already in menopause often complain about a bitter taste in mouth. This is typically due to dry mouth, a common symptom during menopause.
Environmental factors: Exposure to harmful chemicals or toxins can cause bitter taste. The risk particularly increases in people who are exposed to chemicals in occupational settings.
Zinc deficiency: When the body is deprived of zinc, a range of symptoms can manifest, such as a sour or bitter taste, which is one of the common symptoms.
Infections: These include respiratory infections and hepatitis, which are known to cause sour taste and are early symptoms of infection.

Treatment

Mouth sour treatment depends on the underlying conditions, drug interactions with ongoing medications, infections and hormonal transitions. While the sour taste happens as a side effect, when it is persistent, it can affect quality of life. Here are some of the suggestions for mouth sour treatment:

Addressing underlying issues: A sour taste can be a common side effect in acid reflux or conditions such as GERD. Seek guidance from health care professionals for proper diagnosis and treatment. GERD can be managed with lifestyle changes and medications to reduce acid production.
Oral hygiene: Maintaining oral hygiene is a fundamental factor. This can be achieved through regular brushing, dental check-ups and avoiding smoking.
Medication adjustments: If medications are contributing to the sour taste, discuss this with your healthcare provider. They may adjust your prescription or recommend alternative medications.
Dietary modifications: Avoid spicy foods and drinks, and opt for foods that are more neutral or alkaline, such as whole grains, lean proteins and fresh vegetables.
Saliva stimulation: Chewing sugar-free gum or consuming sour candies can help stimulate saliva production and alleviate the sourness. Proper saliva flow aids in neutralising acids and promoting oral health.

Home remedies for managing sour taste in mouth

In addition to medical treatments, some home remedies can provide relief:

Oral rinses: Rinsing your mouth with a mixture of water and baking soda or salt can help neutralise acids and improve oral pH.
Stay hydrated: Adequate hydration is vital. Drinking water throughout the day promotes saliva production, which can naturally wash away acids and bacteria.
Probiotics: Consuming probiotic-rich foods, like yoghurt or kefir, can help maintain a balanced oral microbiome, acting as a remedy for a sour taste in the mouth.

How to prevent sour taste in mouth?

Preventing a sour taste in your mouth involves making lifestyle adjustments that promote long-term oral and overall health:

Be vigilant about your food and beverage choices, especially acidic or sour items. Include dairy products like milk and cheese, which can neutralise acids.
Enhance hydration by sipping on water with lemon or a small amount of apple cider vinegar, which can help balance pH levels.
Establish and adhere to a robust oral care routine. Use fluoride toothpaste to strengthen tooth enamel.
Stress can exacerbate GERD symptoms, leading to a sour taste. Incorporate practices like meditation, yoga or deep breathing exercises into your daily routine to reduce stress.
If you’re taking medications, diligently follow your prescribed regimen. Keep your healthcare provider informed about any side effects, including a persistent sour taste.

Conclusion

A sour taste in the mouth can be caused by several reasons ranging from GERD to poor oral hygiene. Identify the underlying cause and seek an opinion from a health care provider for persistent sour taste signs for proper diagnosis and treatment.

Our Other Specialties