{"id":1068,"date":"2026-04-16T22:58:32","date_gmt":"2026-04-16T22:58:32","guid":{"rendered":"https:\/\/medycyna-gorska.pl\/diamox-acetazolamide-dosing\/"},"modified":"2026-04-16T23:03:41","modified_gmt":"2026-04-16T23:03:41","slug":"diamox-acetazolamide-dosing","status":"publish","type":"post","link":"https:\/\/medycyna-gorska.pl\/en\/diamox-acetazolamide-dosing\/","title":{"rendered":"Diamox (Acetazolamide) \u2014 Dosing for Altitude Sickness Prevention & Treatment"},"content":{"rendered":"\n

Diamox (acetazolamide)<\/strong> is the most commonly used drug for prevention and treatment of altitude sickness \u2014 and one of the most controversial in mountain medicine. Some take it “just in case”, others reject the idea of prophylaxis on principle. As the expedition doctor at Everest Base Camp 2022 and a participant in many trips above 4000 m, I see both sides \u2014 and in this article I’ll give you concrete acetazolamide dosing<\/strong> for prevention and treatment, explain the mechanism of action (carbonic anhydrase), indications, contraindications, interactions, and side effects.<\/p>\n\n\n\n

Dosing in a nutshell<\/h4>\n\n\n\n
    \n
  • AMS prevention:<\/strong> 125 mg twice daily starting 24 h before reaching new altitude, continue through the trip or until adapted.<\/li>\n
  • AMS treatment:<\/strong> 250 mg twice daily until symptoms resolve.<\/li>\n
  • HACE support (after dexamethasone):<\/strong> 250 mg twice daily.<\/li>\n
  • Glaucoma treatment (original indication):<\/strong> 250 mg 2\u20134 times daily.<\/li>\n
  • Epilepsy (registered indication):<\/strong> 250\u20131000 mg\/day in divided doses.<\/li>\n<\/ul>\n\n\n\n

    What is Diamox (acetazolamide) \u2014 mechanism of action<\/h2>\n\n\n\n

    Acetazolamide is a carbonic anhydrase inhibitor<\/strong> \u2014 an enzyme responsible for carbon dioxide metabolism in the body. Blocking this enzyme in the kidneys increases bicarbonate and water excretion, producing a mild metabolic acidosis. This controlled acidosis “tricks” the respiratory center in the brainstem: the brain receives a signal of insufficient oxygen and orders deeper breathing. The effect: better minute ventilation, higher oxygen saturation, faster acclimatization<\/strong>.<\/p>\n\n\n\n

    Acetazolamide is sold under the brand name Diamox (USA, international) and Diuramid (Poland, by Polfa Warszawa) \u2014 250 mg tablets. In clinical practice one 250 mg tablet is halved, so AMS dosing is usually \u00bd tablet (125 mg) twice daily.<\/p>\n\n\n\n

    Indications for acetazolamide<\/h2>\n\n\n\n
      \n
    • Glaucoma treatment<\/strong> \u2014 lowers intraocular pressure. This was the original Diamox indication from which the drug’s career began.<\/li>\n
    • Epilepsy<\/strong> \u2014 as an adjunct drug in certain seizure types, especially in children (catamenial epilepsy).<\/li>\n
    • Acute mountain sickness (AMS)<\/strong> \u2014 registered off-label (but widely used; Wilderness Medical Society Guidelines 2019 endorse its use).<\/li>\n
    • Cardiac\/renal edema<\/strong> \u2014 rarely today, replaced by newer diuretics.<\/li>\n
    • Metabolic alkalosis<\/strong> \u2014 pH correction.<\/li>\n<\/ul>\n\n\n\n

      In mountain medicine acetazolamide is used mainly for prevention and early treatment of AMS<\/strong> (Acute Mountain Sickness). Used prophylactically before the trip, it helps overcome the critical first days of altitude exposure \u2014 when the body slowly retunes ventilation and hemoglobin production.<\/p>\n\n\n\n

      Acetazolamide dosing \u2014 concrete numbers<\/h2>\n\n\n\n

      Preventive dose for altitude sickness<\/h3>\n\n\n\n

      125 mg twice daily<\/strong> (morning and evening) \u2014 start at least 24 hours before reaching a new, significant altitude and continue until full adaptation (or to the end of the trip at higher altitudes). The 125 mg dose equals \u00bd of a 250 mg tablet. Acetazolamide shortens acclimatization time and prevents altitude sickness symptoms. If you plan fast altitude gain \u2014 e.g. a weekend Mont Blanc attempt \u2014 take the first dose 24 hours before the planned climb and continue over subsequent days.<\/p>\n\n\n\n

      In older recommendations you sometimes see 250 mg twice daily preventively \u2014 that’s excessive<\/strong> by current Wilderness Medical Society guidelines. Higher dose doesn’t give better protection, but generates more side effects (paresthesias, taste alteration, diuresis).<\/p>\n\n\n\n

      Therapeutic dose for AMS symptoms<\/h3>\n\n\n\n

      250 mg twice daily<\/strong> \u2014 for developing acute mountain sickness of moderate severity (Lake Louise Score 6\u20139 points). Continue treatment until symptoms resolve + 24 h, combined with rest at the current altitude (no further ascent). If symptoms persist 48 hours or more despite treatment \u2014 descent of 500\u20131000 m is mandatory. With worsening symptoms (altered consciousness, dyspnea at rest) \u2014 discontinue acetazolamide and descend immediately.<\/p>\n\n\n\n

      Dosing in HACE and HAPE<\/h3>\n\n\n\n

      In high altitude cerebral edema (HACE)<\/strong> first-line drug is dexamethasone<\/em> (8 mg, then 4 mg every 6 h), with acetazolamide (250 mg twice daily) added as support. In high altitude pulmonary edema (HAPE)<\/strong> first-line is nifedipine<\/em>, acetazolamide plays an ancillary role. In both cases descent and oxygen are key<\/strong> \u2014 drugs are only stabilizers during evacuation.<\/p>\n\n\n\n

      Dosing in children<\/h3>\n\n\n\n

      In children from 6 years \u2014 2.5 mg\/kg body weight twice daily<\/strong>, max 125 mg per dose. Children below 6 require individual evaluation by a pediatric travel\/mountain medicine physician \u2014 not without reason most organizations don’t recommend high treks (>3500 m) for children below 10\u201312 years.<\/p>\n\n\n\n

      Contraindications and warnings<\/h2>\n\n\n\n
        \n
      • Sulfa allergy<\/strong> \u2014 acetazolamide is structurally related. Cross-reaction in 5\u201310% of patients.<\/li>\n
      • Renal insufficiency<\/strong> (creatinine > 2 mg\/dl) \u2014 drug is renally excreted, accumulates.<\/li>\n
      • Hepatic insufficiency<\/strong> \u2014 especially cirrhosis with encephalopathy.<\/li>\n
      • Metabolic acidosis<\/strong> \u2014 acetazolamide deepens it further (diabetic ketoacidosis, starvation).<\/li>\n
      • Hyponatremia, hypokalemia<\/strong> \u2014 drug worsens electrolyte disturbances.<\/li>\n
      • Pregnancy and breastfeeding<\/strong> \u2014 FDA category C, consider only if necessary.<\/li>\n<\/ul>\n\n\n\n

        Warnings and precautions:<\/strong> insulin-dependent diabetes (acetazolamide may affect glycemic control), nephrolithiasis (accelerates stone formation), closed-angle glaucoma (paradoxically may worsen \u2014 ophthalmology consult). During prolonged use monitor renal and hepatic function. Acetazolamide overdose manifests as aggravated metabolic acidosis, drowsiness, paresthesias \u2014 if concerning symptoms appear check dosing and application and consult a physician.<\/p>\n\n\n\n

        Acetazolamide side effects<\/h2>\n\n\n\n
          \n
        • Paresthesias<\/strong> (tingling in fingers, around the mouth, face) \u2014 occurs in 60\u201390% of patients. Harmless but annoying to some. Resolves after stopping the drug.<\/li>\n
        • Increased diuresis<\/strong> \u2014 passing large amounts of urine, especially in first 2\u20133 days. You must drink more water<\/strong> (additional 1\u20132 l\/day).<\/li>\n
        • Taste disturbance<\/strong> \u2014 metallic taste, “carbonated drinks taste like soap” (classic symptom). Resolves after stopping.<\/li>\n
        • Dizziness, fatigue<\/strong> \u2014 especially at high altitude where we also feel hypoxia symptoms.<\/li>\n
        • Nausea<\/strong> \u2014 rare, mainly at doses >250 mg twice daily.<\/li>\n
        • Hypokalemia<\/strong> \u2014 potassium supplementation with extended use (>2 weeks).<\/li>\n<\/ul>\n\n\n\n

          Serious side effects (rare): Stevens-Johnson syndrome, agranulocytosis, metabolic acidosis, anhedonia syndrome. For skin reactions or systemic symptoms \u2014 discontinue the drug and consult a physician.<\/p>\n\n\n\n

          Acetazolamide drug interactions<\/h2>\n\n\n\n
            \n
          • Aspirin (acetylsalicylic acid)<\/strong> \u2014 at high doses acetazolamide may worsen metabolic acidosis; at normal doses (75\u2013150 mg) clinically insignificant.<\/li>\n
          • Digoxin<\/strong> \u2014 acetazolamide increases potassium excretion, which can potentiate digoxin toxicity.<\/li>\n
          • Lithium<\/strong> \u2014 acetazolamide may increase lithium excretion, reducing therapeutic concentration.<\/li>\n
          • Other diuretics (furosemide, hydrochlorothiazide)<\/strong> \u2014 effects sum up, increased electrolyte disturbance risk.<\/li>\n
          • Amphetamine, pseudoephedrine, mefloquine<\/strong> \u2014 increased concentration of some drugs in blood serum, toxicity risk.<\/li>\n
          • Oral antidiabetic drugs<\/strong> \u2014 increased hypoglycemia risk (rare but possible). Acetazolamide effects on glycemia can be unpredictable.<\/li>\n
          • Folic acid<\/strong> \u2014 acetazolamide may affect absorption; long-term use consider supplementation.<\/li>\n<\/ul>\n\n\n\n

            Dosing individually by indication.<\/strong> Adults and children have different schemes \u2014 pediatric doses proportional to body weight. Acetazolamide is contraindicated in severe renal\/hepatic failure and sulfa allergy. Optimal effect in AMS prevention is achieved when starting 24 hours before altitude exposure.<\/p>\n\n\n\n

            My opinion on acetazolamide prophylaxis \u2014 an expedition doctor’s view<\/h2>\n\n\n\n

            The preventive use of Diamox from the start of a trip is controversial. In my opinion the best and healthiest acclimatization is natural acclimatization without prophylactic drug use<\/strong> \u2014 following the 300\u2013500 m per day ascent rule, with rest days every 1000 m. Pharmacology should be an emergency tool, not a foundation.<\/p>\n\n\n\n

            However, in people who have experienced severe altitude illness in the past<\/strong> (HAPE, HACE, prior AMS requiring evacuation), prophylaxis with acetazolamide 125 mg twice daily from the start of the trip is recommended and justified. Similarly for people doing “fast trips” (weekend Mont Blanc from airplane) \u2014 natural acclimatization is impossible, and pharmacologic prophylaxis saves the trip.<\/p>\n\n\n\n

            If you take acetazolamide preventively \u2014 remember increased diuresis<\/strong>. You drink 2\u20134 l of water + additional 1\u20132 l = total 3\u20136 l\/day. You need a strategy for frequent night bathroom trips (container in the tent), because leaving a warm sleeping bag at -20\u00b0C risks hypothermia and frostbite. That’s not a joke, it’s practical advice that consultants often forget.<\/p>\n\n\n\n

            Frequently asked questions<\/h2>\n\n\n
            \n
            \n
            \n

            How does Diamox work?<\/h3>\n
            \n\n

            Diamox (acetazolamide) is a carbonic anhydrase inhibitor \u2014 an enzyme metabolizing carbon dioxide. It blocks carbonic anhydrase in the kidneys, causing increased bicarbonate excretion and mild metabolic acidosis. Acidosis stimulates the respiratory center in the brainstem, leading to deeper breathing, higher oxygen saturation, and faster acclimatization. Additionally, acetazolamide lowers intraocular pressure (hence use in glaucoma) and stabilizes neuronal membranes (hence use in epilepsy).<\/p>\n\n<\/div>\n<\/div>\n

            \n

            How to take Diamox for altitude sickness?<\/h3>\n
            \n\n

            For altitude sickness prevention: 125 mg (\u00bd of a 250 mg tablet) twice daily \u2014 morning and evening. Start 24 h before reaching new altitude and continue through the trip or until full adaptation. For AMS treatment (Lake Louise Score 6\u20139 points): 250 mg twice daily, until symptoms resolve + 24 h. While taking, increase water intake by 1\u20132 l daily \u2014 acetazolamide is a diuretic. Prefer taking after food to limit stomach discomfort.<\/p>\n\n<\/div>\n<\/div>\n

            \n

            How long can you take Diamox?<\/h3>\n
            \n\n

            In mountain medicine acetazolamide is typically used for 7\u201314 days \u2014 covering the key acclimatization days at altitude. In chronic use (e.g. glaucoma) it can be administered for months, but requires monitoring \u2014 electrolyte, creatinine, and acidosis checks every 1\u20132 weeks. On expeditions over 2\u20133 weeks of continuous use consider potassium supplementation. After returning from the mountains the drug can be stopped without dose reduction \u2014 no dependency.<\/p>\n\n<\/div>\n<\/div>\n

            \n

            Can you take Diamox on an empty stomach?<\/h3>\n
            \n\n

            Diamox (acetazolamide) can be taken both on empty stomach and with food \u2014 but most patients tolerate it better after eating, as it reduces stomach discomfort and nausea risk. In expedition practice the morning dose is taken after breakfast (around 7\u20138 AM) and the evening dose after dinner (around 6\u20137 PM). Avoid taking immediately before sleep \u2014 diuresis may wake you for a bathroom trip.<\/p>\n\n<\/div>\n<\/div>\n

            \n

            Does Diamox cause side effects?<\/h3>\n
            \n\n

            Yes, the most common side effects at doses used in mountain medicine (125\u2013500 mg\/day) are: tingling of fingers and around the mouth (paresthesias) in 60\u201390% of patients, increased diuresis, taste disturbance (metallic taste, carbonated drinks taste \u201ddifferent\u201d), dizziness, fatigue, rarely nausea. Side effects are usually mild and resolve after discontinuation. Rare serious reactions (Stevens-Johnson syndrome, agranulocytosis) occur in <0.1% and require immediate discontinuation and medical consultation.<\/p>\n\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n

            Sources<\/h2>\n\n\n\n
              \n
            • Luks AM, Auerbach PS, Freer L, et al. Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Acute Altitude Illness: 2019 Update.<\/em> Wilderness Environ Med. 2019;30(4S):S3-S18.<\/li>\n
            • Ward M, Milledge JS, West JB. High Altitude Medicine and Physiology<\/em>, 5th edition. CRC Press \u2014 chapter on AMS pharmacology.<\/li>\n
            • Hidalgo J. et al. High Altitude Medicine: A Case-Based Approach<\/em>. Springer, 2023 \u2014 clinical cases of acetazolamide.<\/li>\n
            • Auerbach PS (ed.). Wilderness Medicine<\/em>, 7th edition. Elsevier, 2016 \u2014 chapter “Pharmacology of High Altitude”.<\/li>\n
            • Leaf DE, Goldfarb DS. Mechanisms of action of acetazolamide in the prophylaxis and treatment of acute mountain sickness.<\/em> J Appl Physiol. 2007;102(4):1313-22.<\/li>\n<\/ul>\n\n\n\n

              Medical disclaimer:<\/strong> Acetazolamide (Diamox\/Diuramid) is a prescription drug. Do not use without consultation from a travel\/mountain medicine physician. This article is educational and does not replace individual health assessment. In a life-threatening situation on expedition \u2014 call local emergency services.<\/em><\/p>\n\n","protected":false},"excerpt":{"rendered":"

              Diamox (acetazolamide) is the most commonly used drug for prevention and treatment of altitude sickness \u2014 and one of the most controversial in mountain medicine. Some take it “just in case”, others reject the idea of prophylaxis on principle. As the expedition doctor at Everest Base Camp 2022 and a participant in many trips above […]<\/p>\n","protected":false},"author":2,"featured_media":801,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[49,51,50,45],"class_list":["post-1068","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-medycyna-gorska","tag-acetazolamide","tag-altitude-pharmacology","tag-altitude-sickness","tag-diamox"],"_links":{"self":[{"href":"https:\/\/medycyna-gorska.pl\/en\/wp-json\/wp\/v2\/posts\/1068","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/medycyna-gorska.pl\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/medycyna-gorska.pl\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/medycyna-gorska.pl\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/medycyna-gorska.pl\/en\/wp-json\/wp\/v2\/comments?post=1068"}],"version-history":[{"count":4,"href":"https:\/\/medycyna-gorska.pl\/en\/wp-json\/wp\/v2\/posts\/1068\/revisions"}],"predecessor-version":[{"id":1084,"href":"https:\/\/medycyna-gorska.pl\/en\/wp-json\/wp\/v2\/posts\/1068\/revisions\/1084"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/medycyna-gorska.pl\/en\/wp-json\/wp\/v2\/media\/801"}],"wp:attachment":[{"href":"https:\/\/medycyna-gorska.pl\/en\/wp-json\/wp\/v2\/media?parent=1068"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/medycyna-gorska.pl\/en\/wp-json\/wp\/v2\/categories?post=1068"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/medycyna-gorska.pl\/en\/wp-json\/wp\/v2\/tags?post=1068"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}