Brief Answer: Lot theories , Explained below Detailed Answer: Dear Friend. Hi , I am Dr Anshul Varshney , I have read your query in detail , I understand your concern. Actually a very interesting question it is! Earlier we used to defer the fact that Gastritis (Acidity) has any co-relation with headaches. But the fact is that this happens. Even i see this in my clinical practice. There have been many different theories which tries to explain the reason behind this. But none has been proved with strong evidences. Since you have asked the question , i would say , one or more then one of the following reasons can cause headache in patients with gastritis : 1. Psycological - Most accepted theory. 2. Pain Killers taken for headache can cause gastritis , or caffeine taken for headache can cause gastritis , so it seems both are interlinked. But actually treatment of one is aggravating the other conditions. 3. Neurotransmitter Theory : Vasoactive intestinal peptide (VIP)and neurotransmitters have been described in pathogenesis of migraine headaches. These VIP can also influence the vessels and lower esophageal sphincter, causing symptoms such as dyspepsia, gastritis , reflux. This theory seems to be more logical to me personally , as many people / doctors may claim that there is no co-relation , but i personally feel there is , as lot of patients complains of that. 4. Tension type headaches are associated with gastritis , as tension (stress) can aggravate headache and gastritis both. This is my personal opinion based on details available here. If you still have any query you may please ask me. Stay Healthy. Dr Anshul Varshney , MD

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