Alendronate
bisphosphonate · osteoporosis
Third-party optionBy the Layer Nutrition editorial team · How the atlas classifies the 664 molecules
What this medicine is for
Pharmacologically, Alendronate relates to the category “bisphosphonate (osteoporosis)”. This medicine strengthens the solidity of the bone and reduces the risk of fracture.
In the case of Alendronate, this means: Strengthens bone and reduces the risk of fracture. It is generally taken over the long term, within regular monitoring, and is not stopped on your own initiative.
Under which brands it is found
In France, about 18 reimbursable presentations containing Alendronate are recorded. It is found under several brand names and as generics.
- Acide Alendronique Arrow Lab
- Acide Alendronique Biogaran
- Acide Alendronique Cristers
- Acide Alendronique Eg
- Acide Alendronique Teva Sante
- Acide Alendronique Viatris
- Acide Alendronique Zentiva
- Acide Alendronique/Cholecalciferol (Vitamine D3) Cristers
- Acide Alendronique/Cholecalciferol (Vitamine D3) Eg
- Acide Alendronique/Vitamine D3 Arrow
- Acide Alendronique/Vitamine D3 Teva Sante
- and other presentations
Generics and the original brand are equivalent for the active substance; only the appearance, the name or the excipients may differ.
On the plate: calcium and vitamin D
The treatment acts on bone, but bone needs raw materials. Calcium builds its mineral framework and vitamin D governs its absorption in the intestine. Food provides both, meal after meal.
Calcium is found first in dairy products: yogurt and cheese. Sardines and canned salmon eaten with their bones supply generous amounts, as do kale and broccoli. These foods cover a good share of the skeleton's daily needs.
Vitamin D promotes the intestinal absorption of calcium. It is found mainly in oily fish, salmon, sardines and mackerel, as well as in egg yolk and mushrooms exposed to UV light. Bringing these foods together over the course of the week supports bone.
How alendronate works
Alendronate belongs to the family of nitrogen-containing bisphosphonates. Once in the bloodstream, it binds to the hydroxyapatite crystals that form the mineral of bone, particularly where the tissue is undergoing active resorption. This strong affinity for the skeleton explains its targeted action on bone rather than on the rest of the body.
On site, it enters the osteoclast, the cell responsible for breaking down the bone matrix. Inside, it inhibits an enzyme of the mevalonate pathway, farnesyl pyrophosphate synthase, which is essential for the osteoclast's attachment to the bone surface. Deprived of this anchoring, the osteoclast detaches and its resorptive activity slows. The breakdown of the bone matrix decreases, which gives the tissue time to rebuild.
Why alendronate is prescribed
Alendronate is indicated for the treatment and prevention of postmenopausal osteoporosis. It is also used to increase bone mass in men with osteoporosis, to treat corticosteroid-induced osteoporosis and Paget's disease of bone. The common thread in these situations is bone that breaks down faster than it rebuilds.
By slowing resorption, alendronate prevents bone loss and increases the mineral density of bone. Denser bone withstands stress better and breaks less easily. Reducing the risk of fracture is the ultimate goal of treatment, and it is against this horizon that its value is judged.
How to take it day to day
The tablet is taken in the morning, right after getting up, on an empty stomach, at least 30 minutes before the first food, the first drink or any other medication. It must be swallowed with a large glass of still water, 180 to 240 mL, and never with coffee, tea, juice, mineral water or milk, because these drinks reduce its already low absorption. After taking it, you must stay standing or sitting upright, without lying down, for at least 30 minutes and until the first meal, to limit irritation of the esophagus.
This discipline in dosing determines the effectiveness: taken incorrectly, the tablet does not pass through and does not work. The treatment is a long-term one and should not be stopped on your own initiative, even if the bone gives no sign of trouble. The terminal half-life of alendronate exceeds ten years, because it is released very slowly from the skeleton: its effect sets in and continues well beyond each dose.
The effects to know about
The most frequent effects involve the upper digestive tract. In clinical trials, abdominal pain was reported in 1.5 to 6.6 % of patients, acid regurgitation in 1.1 to 4.3 %, dyspepsia in 1.1 to 3.6 % and nausea in 1.1 to 4.0 %. Esophageal ulcer remained rarer, from 0 to 1.5 %, and musculoskeletal pain affected 0.3 to 4.1 % of patients. These figures explain the dosing instructions, which aim to protect the esophagus.
Osteonecrosis of the jaw occurs with an incidence of about 1 in 10,000 to 1 in 100,000 in patients treated for osteoporosis, often after a tooth extraction or a local infection, which justifies dental monitoring. Atypical femoral fracture, in the shaft or the subtrochanteric region, may appear after prolonged treatment and should be considered when there is unusual thigh pain.
Why calcium and vitamin D matter
Alendronate slows the destruction of bone, but mineral reconstruction needs available calcium. This is why hypocalcemia is a contraindication: it must be corrected before starting treatment. A vitamin D deficiency warrants supplementation before and during use, because vitamin D governs the body's calcium homeostasis.
Vitamin D promotes the intestinal absorption of calcium: without it, the calcium supplied is poorly used. An adequate intake of calcium remains necessary for bone health throughout the treatment as well. This nutritional foundation accompanies the medication, in addition to your treatment and never in place of it, and food is its first supplier.
Interactions and monitoring
Calcium, antacids and medications containing polyvalent cations, such as calcium, magnesium, iron or aluminum, reduce the absorption of alendronate: their intake must be spaced apart from that of the tablet. Caution is also recommended with aspirin and non-steroidal anti-inflammatory drugs, because of an increased risk of gastrointestinal irritation when they are combined.
Laboratory monitoring frames the treatment. It includes serum calcium and bone mineral density at the outset, then a check at 6 to 12 months, with monitoring of magnesium and phosphorus. Alendronate is not advised in cases of severe renal impairment, below a creatinine clearance of 35 mL/min, which means checking kidney function before prescribing it.
Sources
Related molecules
To explore within the « Bones and joints » family and its neighbours.
See the entire « Bones and joints » family · Back to the atlas
Supplements to consider
Beyond the plate, a single isolated nutrient can be worth discussing, to confirm with your doctor or pharmacist. Here is which one and in which form.
Calcium
Calcium is the most abundant mineral in the body, involved in bone health. Calcium citrate is well absorbed, including away from meals, whereas carbonate requires an acidic environment for its absorption.
Preferred form calcium citrate (does not depend on gastric acidity)
Vitamin D3 (cholecalciferol)
Vitamin D is a fat-soluble vitamin. The D3 form (cholecalciferol) is the one adopted by most guidelines. It is better absorbed when taken during a meal that contains fats.
Preferred form D3 (cholecalciferol), during a fatty meal
Frequently asked questions
How do you take alendronate?
According to the leaflet, alendronate is taken on an empty stomach, first thing in the morning, swallowed whole with a large glass of plain water, while staying standing or sitting for a while before eating or drinking anything else. For the exact schedule that applies to you, refer to your medicine's leaflet and follow the advice of your doctor or pharmacist.
What are the side effects of alendronate?
The leaflet notably mentions digestive problems and irritation of the oesophagus or stomach, which is why the way it is taken is so specific. The complete list and the frequency of these effects are given in the leaflet. If you experience discomfort or pain, talk to your doctor or pharmacist.
Can you take alendronate with calcium or food?
No: the leaflet states that calcium, supplements, antacids and food reduce the absorption of alendronate when they are taken too close together, and it recommends spacing them out. The precise timing of your various doses should be set with your doctor or pharmacist.
Can you take alendronate during pregnancy or breastfeeding?
Alendronate is an osteoporosis treatment reserved for very specific situations, and the leaflet includes specific warnings regarding pregnancy and breastfeeding. This decision rests with your doctor: tell them about any current or planned pregnancy before any treatment.
Why are calcium and vitamin D often taken alongside alendronate?
The leaflet for alendronic acid notes that an adequate intake of calcium and vitamin D is important during this type of treatment, as these two nutrients contribute to the maintenance of normal bone. That is the nutritional angle to consider, while monitoring your status with the professional who follows you.
Which forms of calcium and vitamin D are well absorbed?
For calcium, calcium citrate is a form reputed to be well absorbed, including outside of meals. For vitamin D, vitamin D3 (cholecalciferol) is the form best used by the body. The key is still to space these intakes apart from taking the medicine, as the leaflet reminds you.
Ces réponses portent sur le volet nutritionnel. Pour toute question sur votre médicament, la notice et votre médecin ou pharmacien font foi.