Digestive Health Heartburn Symptoms Causes of a Sour or Bitter Taste in the Mouth By Sharon Gillson Sharon Gillson Sharon Gillson is a writer living with and covering GERD and other digestive issues. Learn about our editorial process Updated on November 17, 2021 Medically reviewed by Priyanka Chugh, MD Medically reviewed by Priyanka Chugh, MD LinkedIn Priyanka Chugh, MD, is board-certified gastroenterologist with a background in internal medicine. She practices with Trinity Health of New England in Waterbury, Connecticut. Learn about our Medical Expert Board Print Table of Contents View All Table of Contents Medications Zinc Deficiency GERD Other Causes Coping Having a bitter, sour, or foul taste in your mouth may be a reaction to something you ate. It's not uncommon to suddenly "burp up" something that didn't agree with you. However, this symptom can be worrisome if it happens frequently. Three of the more common causes of a bad taste in the mouth are: Gastroesophageal reflux disease (GERD) Medications, including chemotherapy Zinc deficiency Any change in the typical taste perception is known as dysgeusia. It is one of several conditions that affect the taste. Other taste disorders include hypogeusia (the loss of taste sensitivity) and ageusia (the complete loss of taste). Diagnosing dysgeusia can sometimes be challenging. It often requires ruling out all other causes first. Verywell / Laura Porter Finding the proper treatment can be a process of trial and error. In some cases, the condition may resolve on its own. Other times, it may require treatment to resolve the underlying cause. This article explains the common causes of bitter taste in the mouth and how they are diagnosed and treated. Medications According to research published in the journal Canadian Family Physician, at least 250 different drugs can cause a bitter taste in the mouth. It's theorized that this occurs because of: How drugs impact the taste receptors in the brainThe taste of medicines when mixed with salivaA phenomenon where a drug molecule circulating in a blood vessel of the tongue interacts with taste bud receptors Some of the more common culprits include: Antibiotics: Including ampicillin, macrolides, quinolones, sulfamethoxazole, trimethoprim, tetracycline, and metronidazole Heart medications: Including many high blood pressure medications, diuretics, statins, and antiarrhythmics Chemotherapy drugs: Including cisplatin, cyclophosphamide, and etoposide Neurologic medications: Including antiparkinson drugs, migraine medications, and muscle relaxants Psychotropic drugs: Including most tricyclic antidepressants, some antipsychotics, anti-anxiety drugs, mood stabilizers, and hypnotics Other prescription and over-the-counter (OTC) drugs: Including thyroid drugs, antihistamines, bronchodilators, anti-inflammatories, smoking cessation aids, antifungals, and antivirals What Causes a Metallic Taste in Your Mouth? Diagnosis and Treatment Doctors typically diagnose drug-induced sour taste after excluding other things. Healthcare providers will often start by checking for: Infection Cancer Nutritional deficiencies Acid reflux Based on the timing of the symptoms, your doctor may be able to pinpoint the drug causing the problem. They may even be able to decipher it after reviewing other medications you are taking. Then, if appropriate, the offending drug might need to be stopped or substituted. In some cases, taking a dose at night instead of during the day may help reduce the bitter taste in your mouth. However, if it is related to a drug you're using for a short period, such as an antibiotic, you may need to bear with the unpleasant taste until treatment is complete. Never stop taking a medication before speaking with your healthcare provider. Instead, work with your doctor to determine if a medication is causing your bitter taste. They will help you identify what may be to blame and, if possible, change the drug or alter the dose. Recap Medications, including antibiotics, heart medication, chemotherapy, and some other prescription and OTC drugs, can cause a sour taste in the mouth. Your doctor can help determine if that's the case for you and if a change can be made. Zinc Deficiency Zinc deficiency is one of the more common causes of taste disturbances. The sour taste associated with zinc deficiency is often difficult to describe. Some use terms such as "strange," "off," or simply "bad." While the exact cause is unknown, zinc increases the concentration of a protein known as gustin. Since the body uses this protein to produce taste buds, it's possible that a lack of it could lead to problems with taste. A zinc deficiency may be caused by: Lack of zinc in a diet Poor absorption of zinc in the intestines Alcohol Chemotherapy Thiazide diuretics, drugs that increase urine output Capoten (captopril), an ACE inhibitor used for high blood pressure and other issues Cuprimine (penicillamine), used to treat kidney stones Malnutrition In addition, zinc deficiency is associated with certain diseases. They include: Cancer Celiac disease Chronic kidney disease Crohn's disease Diabetes Liver disease Pancreatitis Sickle cell disease Ulcerative colitis IBD and Zinc Deficiency Diagnosis and Treatment Doctors diagnose zinc deficiency by measuring the concentration of zinc in a sample of blood. If you are low, your doctor may suggest that you increase zinc in your diet. Foods naturally high in zinc include: ShellfishRed meatBeans and legumesEggsDairy While a daily zinc supplement may help normalize blood levels, it won't resolve what caused low levels in the first place. For a long-term resolution, however, it's essential to identify the cause. For example, if a medication causes a zinc deficiency, you may need to work with your doctor to stop, substitute, or adjust the dose of the offending drug. Figuring this out is often a process of trial and error. Your doctor will consider your age, weight, medical history, health status, current drug use, and co-occurring symptoms as they evaluate potential causes. While you can often resolve zinc deficiency by taking supplements, it's a good idea to find out why your body is low on zinc. Learning the cause will allow you to resolve the problem long-term. Recap A lack of zinc can result in a bad taste in your mouth. Zine deficiency has several possible causes, so treating it requires working with your healthcare provider to determine what's behind the deficiency in your case. GERD The lower esophageal sphincter (LES) sits at the bottom of the esophagus. These group of involuntary muscles contract to keep the acid in your stomach from coming back into your throat. Usually, the LES functions as a one-way valve. However, with gastrointestinal reflux disease (GERD), it suddenly relaxes. This causes the LES to open when it shouldn't, allowing stomach acid to flow back into the esophagus. Known as acid reflux, this can cause a sour or bitter taste, as well as: Heartburn Chest pain Bad breath Burning in the throat Difficulty swallowing The sensation of a lump in the throat Coughing Hoarseness You can usually pinpoint GERD as the cause of a sour or bitter taste if it co-occurs with heartburn and develops soon after eating. Still, see your healthcare provider for an evaluation and formal diagnosis. Acid Reflux Triggers Common triggers of acid reflux include:SmokingAlcoholCaffeineFatty foodsAcidic foodsEating large meals Pregnancy and obesity can also contribute to GERD. That's because, in both situations, excess weight places stress on the stomach and esophagus. A hiatal hernia (stomach hernia) can have a similar effect. This occurs when part of your stomach pushes through your diaphragm. As the stomach pressed upward, it can change the position of the LES so that it has trouble staying shut. Diagnosis and Treatment To diagnose GERD, your doctor may suggest the following: Endoscopy, a procedure that allows for examination of the LES Manometry, a test that measures the contractions of the esophageal muscles Ambulatory pH probe in which a swallowed probe measures how and when reflux occurs Treatment typically involves a combination of OTC and prescription medications. These include: Antacids H2 blockers like Prilosec (omeprazole) Proton pump inhibitors (PPIs) like Nexium (esomeprazole) Lioresal (baclofen) to help strengthen the LES muscles Changes in diet, weight loss, and quitting smoking can also help. It may take some time to identify which foods or activities trigger your acid reflux. Therefore, sometimes effectively treating GERD requires limiting or avoiding certain foods and taking OTC or prescription medications. The good news is that once you control GERD symptoms, the sour or bitter taste sensations should also go away. Recap Sour taste occurring alongside heartburn that occurs shortly after eating is a sign that the bad taste in your mouth may be from GERD. OTC or prescription medication may be needed. Other Causes Other conditions may change your taste perception or make an existing disorder more pronounced. These include: Cigarette smoking, which dulls the taste and makes food less palatable Xerostomia (dry mouth syndrome), which alters taste perception Dehydration, which leads to a dry mouth and affects the taste Anxiety and stress, which can lead to a dry mouth and change the way things taste Infection or illness Oral candidiasis (thrush), a yeast infection in the mouth/throat Poor dental hygiene Pregnancy, especially during the first trimester Menopause, which may alter taste due to changes in hormone levels Brain injury or surgery, which can trigger phantom taste sensations Neurologic (nerve-related) disorders such as epilepsy, multiple sclerosis, Bell's palsy, brain tumors, and dementia Radiation therapy of the head and neck, which can damage salivary tissues Lead poisoning, often recognized by a characteristic blue line along the gums Pine nut syndrome, which can cause a bitter taste that may occur one to three days after eating pine nuts Burning mouth syndrome, which can also cause a burning or scalding sensation in the mouth Why You Have a Dry Mouth Coping Whatever the underlying cause of bitter taste, you can do things to help reduce the symptoms. Some practical home remedy tips include: Drink plenty of water, which can hydrate your mouth and cause you to urinate. Frequent urination can help flush out impurities that may be contributing to your symptoms. Adding a little lemon juice to your water may also help reduce the bad taste in your mouth. Chew sugar-free gum to increase saliva production. Practice good oral hygiene, including getting regular dental checkups and using an antibacterial mouthwash. Rinse your mouth with a half-teaspoon of salt plus a teaspoon of baking soda added to a glass of water, which may help reduce the bitter taste. Avoid spicy or fatty foods, which promote acid reflux. Even if GERD is not the cause of the bad taste in your mouth, the reflux of stomach acid will only worsen your symptoms. Stop smoking. Whatever the underlying cause of sour taste, smoking will only amplify the effects. Even With a Dry Mouth, You Can Eat Well Summary Dysgeusia is the medical term for a change in the usual taste perception. Often this disorder is associated with a bitter or sour taste in the mouth. Many things can cause a bitter taste in the mouth, including medications, nutritional deficiencies, GERD, other health conditions that lead to a dry mouth. Treatment depends on the cause, but you can address symptoms in the short term by drinking lots of water, maintaining good oral hygiene, and quitting smoking. 11 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Clarrett DM, Hachem C. Gastroesophageal Reflux Disease (GERD). Mo Med. 2018;115(3):214-218. Rehwaldt M, Wickham R, Purl S, et al. Self-care strategies to cope with taste changes after chemotherapy. Oncol Nurs Forum. 2009;36(2):E47-56. doi:10.1188/09.ONF.E47-E56 Pisano M, Hilas O. Zinc and Taste Disturbances in Older Adults: A Review of the Literature. Consult Pharm. 2016;31(5):267-70. doi:10.4140/TCP.n.2016.267 Douglass R, Heckman G. Drug-related taste disturbance: a contributing factor in geriatric syndromes. Can Fam Physician. 2010;56(11):1142-7. Grattan BJ, Freake HC. Zinc and cancer: implications for LIV-1 in breast cancer. Nutrients. 2012;4(7):648-75. doi:10.3390/nu4070648 Maxfield L, Crane JS. Zinc Deficiency. StatPearls Publishing. Martinucci I, De bortoli N, Giacchino M, et al. Esophageal motility abnormalities in gastroesophageal reflux disease. World J Gastrointest Pharmacol Ther. 2014;5(2):86-96. doi:10.4292/wjgpt.v5.i2.86 Kuga M. A study of changes in gustatory sense during pregnancy. Nippon Jibiinkoka Gakkai Kaiho. 1996;99(9):1208-1217,1235. doi:10.3950/jibiinkoka.99.1208 Dutt P, Chaudhary S, Kumar P. Oral health and menopause: a comprehensive review on current knowledge and associated dental management. Ann Med Health Sci Res. 2013;3(3):320-3. doi:10.4103/2141-9248.117926 Pearce JM. Burton's line in lead poisoning. Eur Neurol. 2007;57(2):118-9. doi:10.1159/000098100 Risso DS, Howard L, Vanwaes C, Drayna D. A potential trigger for pine mouth: a case of a homozygous phenylthiocarbamide taster. Nutr Res. 2015;35(12):1122-5. doi:10.1016/j.nutres.2015.09.011 Additional Reading Badillo R, Francis D. Diagnosis and treatment of gastroesophageal reflux disease. World J Gastrointest Pharmacol Ther. 2014;5(3):105-12. doi:10.4292/wjgpt.v5.i3.105 Syed Q, Hendler K, Koncilja, K. The Impact of Aging and Medical Status on Dysgeusia. Amer J Med. 2016;129(7):e1-e753. doi:10.1016/j.amjmed.2016.02.003. By Sharon Gillson Sharon Gillson is a writer living with and covering GERD and other digestive issues. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? 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