Zoledronic Acid (Reclast, Zometa)

Brand name: Reclast®, Zometa®  

Generic name:Zoledronic Acid  

Other names: zoledronate, Zomera, Aclasta 

Therapeutic Class: bisphosphonates
(or diphosphonate) 

Manufacturer / Distributor: Novartis 

FDA Approval: Zometa (Zoledronic Acid) was approved by the US Food and Drug Administration (FDA) for Treatment of Cancer-Related Bone Complications; other indications were subsequently approved. 

Availability: Zoledronic Acid is available by prescription only 

Indications: Zoledronic acid is used to treat hypercalcemia (high blood calcium) caused by cancer with or without metastases. The drug is also used as prevention of complications (fracture of a bone, or bone pain that requires surgery or radiotherapy) due to the spread of cancer to bones (bone metastases) from different types of tumors. Zoledronic acid is also used in the treatment of Paget's disease of bone (a condition in which the bones become painfully enlarged and deformed), or a form of cancer of the bone marrow called multiple myeloma.  

Along with the drug, you may be recommended to take calcium supplement and a multivitamin containing vitamin D to prevent bone damage. Zoledronic acid may be recommended for other medical conditions that are not mentioned in this article; talk to your doctor or pharmacist for more information.  

Dosage form: Zoledronic Acid is given by injection into a vein 

Dosage: it is important that zoledronic acid be administered by an oncologist or health care professional with experience in chemotherapy drugs. The drug must be injected over a period of within 15 minutes. Zoledronic acid may cause severe kidney problems or, possibly, renal failure in overdose (not more than 4 mg), or when the length of the injection is not respected.   

Usually, the recommended dose of zoledronic acid in the treatment of hypercalcemia (increased calcium concentration in the blood) induced by cancer with or without metastases is 4 mg, administered as a single infusion dose intravenously over a period of less than 15 minutes. Before each treatment, your health care provider will assess your blood calcium and serum creatinine to determine the outcome of the treatment and your kidney function. If the calcium in the blood does not decrease to normal levels, you will receive a second dose in about 7 days following the first dose.  

In the treatment of osteoporosis, zoledronic acid is usually administered once a year. In the case of Paget's disease, zoledronic acid is taken as a single dose. Your doctor may change the dosage, if he thinks it will be helpful. The recommended dose of zoledronic acid in the treatment of multiple myeloma is 4 mg, taken by infusion over at least 15 minutes, every 3-4 weeks.  It is important to drink plenty of water within a few hours before receiving zoledronic acid. The optimal duration of treatment will be determined by your doctor depending on your medical condition.  

Overdose: zoledronic acid must be given exactly as directed by a health professional that has experience in chemotherapy drugs. In fact, not only zoledronic acid, but taking any medication in the right dose is the first step to better treatment. An overdose of zoledronic acid may cause serious kidney problems. Contact your doctor immediately if you experience these warning signs of overdose:  

• seizures 
• confusion 
• double vision 
• shortness of breath 
• sudden tightening of muscles 
• muscle cramps or/and weakness 
• fast, pounding, or irregular heartbeat 
• difficulty walking or/and speaking  
• Numbness, burning, or tingling in fingers or toes.  

Missing dose: Avoid missing dose; undergo the therapy exactly as recommended by your doctor.  By taking zoledronic acid on time and completely is the best way to get good results from it. Therefore, be present at each appointment to take all the prescribed doses. If for some reasons you cannot go to the hospital for the treatment, contact your oncologist before the date schedule for the injection. If in spite of your efforts you miss an appointment, call your doctor as soon as possible.  

Contraindication: Zoledronic acid is contraindicated or should be used with precaution in the following conditions: 

• allergy to the drug or one of the components 
• pregnancy – child-bearing age females must use a reliable method of birth control to prevent pregnancy 
• breast feeding  
• Children.    

Taking zoledronic acid requires particular attention in patients suffering from these medical conditions: 

• hypocalcemia - abnormally low serum calcium levels in the blood.  
• hypomagnesemia – abnormally low level of magnesium in the blood 
• hypophosphatemia - abnormally low level of phosphorus in the blood 
• dehydration  
• kidney failure or other severe kidney damage 
• liver failure  
• heart failure 
• Recent dental surgery – the therapy can cause serious problems with the jaws.                                                                           

Mechanism of action (MOA): zoledronic acid is a bisphosphonate derivative; it works by increasing bone density, slowing bone breakdown and decreasing the amount of calcium released from the bones into the blood.  

Interactions:  if you are taking zoledronic acid, tell your doctor before taking vitamins, nutritional supplements, St. John's wort. Some medications can alter the effects of zoledronic acid, or increase the risk of side effects. Tell your doctor or pharmacist before taking any of these medications:  

• Thalidomide  
• acetylsalicylic acid (Aspirin) 
• calcium-containing IV solutions 
• aminoglycosides: (tobramycin, gentamicin, and others) 
• Platinum-based chemotherapy agents  
• bisphosphonates (clodronate, alendronate, risedronate, etidronate, and others)  
• angiotensin-converting enzyme (ACE) inhibitors (captopril, perindopril, ramipril, and others)  
• anti-inflammatory drugs (naproxen, ibuprofen, diclofenac, and others)  
• Diuretics (‘water pills') such as bumetanide (Bumex), Ethacrynic acid (Edecrin), and furosemide (Lasix).  

Side effects: In addition to attacking cancer cells, zoledronic acid also affects some normal cells and cause adverse effects in most patients. Most common zoledronic acid side effects include : 

• intense thirst  
• diarrhea 
• bone or joint pain 
• swollen legs  
• fatigue 
• white vaginal discharge  
• hair loss 
• heartburn 
• fever 
• headaches  
• loss of appetite 
• loss of weight  
• nausea and vomiting  
• difficulty falling asleep or staying asleep  
• white patches in the mouth 
• redness of the eye or excessive tearing 
• redness or swelling at the injection site 
• Numbness, burning, or tingling in fingers or toes.   

If the side effects above persist for weeks, contact your oncologist. In addition, contact your doctor if you experience any of these symptoms: 

• chest pain  
• painful or swollen gums 
• Poor healing of the gums
• loosening of the teeth 
• irregular heartbeat 
• numbness or the feeling of heaviness in the jaw 
• signs of infections: rash, hives, itching, fever, sore throat  
• swelling of the eyes, face, lips, tongue and/or throat 
• swelling of the hands, arms, feet, ankles, and/or lower legs
• difficulty breathing or swallowing 
• numbness or tingling around the mouth 
• sudden tightening of muscles 
• Unusual bruising or bleeding.  

References: 

http://www.pharma.us.novartis.com/product/pi/pdf/Zometa.pdf