I have a confession to make: early last year I accidentally “killed” my boss’ beautiful Cristate Organ Pipe cactus. It was a beautiful succulent, a cristate morph that had grown into a mini organ pipe. It was about 10 years old and was growing well when I started fussing with it and interfering in its care.

I thought I was being attentive, giving it a sip of water every few days over the period of a couple months. Turns out I was “killing it with kindness”, as the roots developed rot from overwatering and the cactus began to turn soggy and disintegrated. A quick search on Google revealed that the watering schedule for these cacti is less than 200 mL every 4 weeks.

I’m not looking for sympathy for sharing this story, nor was I punished for killing the cactus (unless you count writing blogs as punishment). However, I want to draw a parallel between adherence to watering schedules and adherence to medication therapy. When we water our plants, oftentimes what really matters is the soil’s moisture content over time. Overwatering means that the soil remains saturated with water; suffocating the roots while allowing microorganisms to grow. Underwatering means that the roots experience periods of drought, which dry out the roots, forcing the plant to prune unneeded root growth in a slow regression.

Interestingly, medication efficacy and therapies are very similar. Just like a watering schedule, medications are prescribed with dosages and frequency, “one tablet daily, one tablet twice a day, etc.” The reason for this is similar to the idea of moisture saturation in the soil.

Medications have a narrow therapeutic range, and the frequency and dosage of the medication regimen are designed to keep drug levels at an effective range in the body. Missing a dose of medication is like underwatering. Therapeutic levels of the medication in the body fall below the necessary ranges and become ineffective, allowing the disease to progress just like when the soil gets too dry and the growth regresses. Ok, great. Don’t overwater cacti, don’t miss a dose of your medication, nothing groundbreaking here.

Oral bisphosphonates like Alendronate and Ibandronate are not groundbreakingly new, there is proven efficacy in their use for the treatment of postmenopausal osteoporosis. However, some patients report side effects of gastric esophageal reflux disease when taking this medicine. GERD causes stomach acids to regurgitate up towards the esophagus, causing erosion and pain. This leads to patients’ reluctance to take their medications as prescribed, the epitome of underwatering/overwatering cycle. I am writing to you now to tell you about Zoledronic Acid infusion by IV.

Zoledronic Acid is a bisphosphonate, but rather than taken orally, it is administered by IV infusion. The benefit is that instead of taking an oral medication daily or weekly, Zoledronic Acid is given by IV infusion once a year. Once administered into the body, zoledronate retains its effectiveness for one full year or more. If we apply the metaphor, it maintains moisture levels in the soil of your body (therapeutic medication levels in your bones), and prevents the fluctuation of missing doses of oral bisphosphonates.

Imagine now our office’s cacti. Imagine that instead of struggling with an inconsistent watering regimen, I installed a controlled water infusion system to maintain soil moisture levels. It would still be alive and thriving now.

The same can be said for our bone health. If you are currently struggling with GERD while taking oral bisphosphonates for your bone health, consider switching to a Zoledronic Acid IV infusion once a year.

A study by Al-Bogami et al., found that patients treated with zoledronic acid obtained better clinical outcomes after treatment when compared with oral bisphosphonates. Al-Bogami found that “The BMD of the total hip decreased after 2 years in patients receiving alendronate by 0.4% from the baseline, whereas in the zoledronate-treated group, it increased by 0.8% . The BMD at the lumbar spine increased after 2 years in patients receiving alendronate by 3.6%, and zoledronate by 5.7%. The increase in BMD at both sites was significantly greater in patients receiving zoledronate compared with patients receiving alendronate (p=0.001).”(Al-Bogami et al., 2015). This finding establishes that Zoledronic Acid is more effective in treating osteoporosis in the femoral neck and lumbar spine when compared to its oral bisphosphonate equivalent.

Every medication comes with its side effects and concerns; Zoledronic acid is no different. The same study by Al-Bogami found that “It is also important to mention that renal deterioration progressing to renal failure has been observed by other investigators ...[approximately] 8 weeks [after] zoledronate administration in some patients.29 Zoledronate is, therefore, contraindicated in patients with renal impairment, and all patients administered with zoledronate should be monitored for renal function regularly as a precautionary measure.”

References:
Al-Bogami, M. M., Alkhorayef, M. A., Bystrom, J., Akanle, O. A., Al-Adhoubi, N. K., Jawad, A. S., & Mageed, R. A. (2015). Favorable therapeutic response of osteoporosis patients to treatment with intravenous zoledronate compared with oral alendronate. Saudi Medical Journal, 36(11), 1305–1311. https://doi.org/10.15537/smj.2015.11.12731

Oral Bisphosphonates vs. Zoledronic Acid: Which one is right for you?