In 2006 I had a complete thyroidectomy and suffered some parathyroid complications. Read more about my thyroid story HERE. Pea-sized parathyroid glands (two on each side of your thyroid) sit directly adjacent to the two thyroid lobes in your neck. Parathyroid glands produce parathyroid hormone, which regulates calcium levels in the blood. Even small changes in blood calcium levels can have a drastic effect on muscles and nerves. My post-surgery report concluded that my parathyroids were not removed and that they must have been damaged or compromised in some way. After spending a week in the hospital, my calcium levels were finally stabilized with large doses of calcium and calcitriol. Over the next few years, my parathyroids recovered slightly and I was able to stop taking loads of calcium. In the last 6-7 years my parathyroids have mostly stopped doing their work and I have become more and more dependent on regular calcium supplements. I currently take about 1500mg of calcium spaced over three doses during the day. I take a combination of elemental calcium (from microcrystalline hydroxyapatite) and calcium citrate. Even with all this calcium, I’m lucky if my blood test results are around 8.2 mg/dL, just below the normal range.
I learned a very big lesson on my Nepal 2022 Gokyo-Cho La Pass-Everest Base Camp trek about hypocalcemia while taking diamox. In hind sight, it seems quite obvious but it had not occurred to me nor had any doctor ever cautioned me. Diamox is a diuretic medication which treats swelling and removes excess water from your body. It’s used for things like heart disease, seizures, edemas, glaucoma, and altitude sickness. Diamox is used as an altitude sickness medication because it increases the production of urine which helps excrete water and salt (but also other ions like calcium) from your body. Drinking lots of water also helps with altitude acclimatization. I had tried to get an appointment at my local clinic for diamox and other travel medications but was told that wasn’t a legitimate reason for an appointment. And even if I had gotten an appointment would the doctor or nurse practitioner have caught it?
In 2019, I was prescribed and took diamox while I was on Mt. Kilimanjaro (19,341 ft). It’s something that most people take as a precaution for altitude sickness even though they don’t know if they need it or not. I took it as a precaution even though I’ve never had trouble at higher elevations. I’ve hiked many times in the Sierra Nevada Mountains summiting Mt Whitney (14,505 ft.) and crossing Forester Pass (13,200 ft.) and spending weeks at a time over 10,000 ft. Just a week before Mt. Kilimanjaro I was in Rwanda to visit Dian Fossey’s grave and old Karisoke Research Center and easily hiked to an elevation of 10,100 ft. But successful past experience doesn’t mean that the next time is going to be without incident. Mt. Kilimanjaro was an 8 day trip and I suffered no obvious ill side effects from taking diamox. It’s also worth noting that in 2019 I was less dependent on calcium and was taking a smaller dose.
LOL, I don’t usually get pictures of myself when I’m feeling unwell but I guess I look something like this. Pictures from Pacific Crest Trail 2009, Mt. Kilimanjaro 2019 and PCT 2017.
I got some diamox in Nepal (you can buy it over the counter) and started taking it on day 1 of my trip. By day 6, my digestive tract was super unhappy. I had either eaten some bad vegetables or was reacting to the oil used to cook the food. I felt really poorly and had little energy on days 6 and 7 but by the morning of day 8 I was starting to wonder if I was also suffering from low blood calcium. The tricky part is that one of the side effects of diamox is tingling, especially in your feet. Tingling is also a side effect of low blood calcium. I definitely had strong, periodic tingling in my feet but I was also experiencing tingling in my face and lips. On the morning of day 8, the muscles in my right thumb were also frozen into place. During breakfast I asked members of my group if they noticed evidence of the Chvostek sign when I tapped my face. Results were inconclusive but by the end of the day I was convinced that my blood calcium level was acutely low. Over the period of those 8 days, I was excreting calcium in my urine at a dangerous rate.
My calcium levels at their best are already below the normal range so I have a small window before I’m in trouble. Severe hypocalcemia is generally defined as serum levels less than 7.6 mg/dL and considered a medical emergency due to the cardiac risk of heart arrhythmia and seizures. I barely got any sleep the night of day 8 and by the morning of day 9 I felt disoriented and weak and not really present in my body. I was having a hard time deciding what order in which to do things and what clothes to put on. A giant hiking day was ahead of me and I had to make the big decision of continuing on the trek or getting a helicopter back to Lukla. Read my day 9 blog for all the details. One group member had to leave us via helicopter on day 6 and it was a bummer way for her trek to end (pics below). I discontinued use of diamox the morning of day 9 and had already started ramping up my calcium intake to 500mg every four hours over the previous night. After five hours of hiking and climbing 2,244 ft. to an elevation of 17,614 ft., I was already starting to feel a bit better and wanted to eat a snack atop Cho La Pass. I doubt I could have made it without help carrying my gear. Over the next few days I started to feel better and the tingling in my face and lips stopped and my muscles were no longer contracting and locking into place (tetany). Despite my challenges with food and eating very few calories, my energy levels improved slightly.
Day 6: Gokyo Bubbles
Day 7: Need A Boost – Gokyo Ri
Day 8: Tibetan Snowcock Serenade Across The Ngozumpa Glacier
Day 9: Still I Rise To Cho La Pass
Obviously I’m not a doctor and I’m not giving medical advice. If you suffer from hypocalcemia, take large doses of calcium and are prescribed diamox (acetazolamide) it’s worth having a discussion with your doctor. I don’t have medical evidence to prove my experience but I know my body well enough to interpret my symptoms. The interesting part is that if I’d never been to the ER due to low blood calcium levels I wouldn’t have known what it felt like. There were two clients who are doctors in my group and even they immediately questioned how I could know that I had low blood calcium. After my explanation they still didn’t seem convinced. The guides for my group could not help me medically. The doctors in my group could not help me medically. I had to know how to help myself! Above all, know your body and trust what it is telling you!