PARICALCITOL Drug Interactions: What You Need to Know

INTERACTIONS Table 4 includes clinically significant drug interactions with Paricalcitol Injection.

Table

4: Clinically Significant Drug Interactions with Paricalcitol Injection Drugs that May Increase the risk of Hypercalcemia Clinical Impact Concomitant administration of high doses of calcium-containing preparations or other vitamin D compounds may increase the risk of hypercalcemia. Thiazide diuretics are known to induce hypercalcemia by reducing excretion of calcium in the urine.

Examples

Calcium-containing products, other vitamin D compounds or thiazide diuretics Intervention Monitor calcium more frequently and adjust Paricalcitol Injection dose as needed [see Warnings and Precautions (5.1) ] .

Digitalis Compounds Clinical Impact Paricalcitol

Injection can cause hypercalcemia which can potentiate the risk of digitalis toxicity.

Intervention

Monitor patients for signs and symptoms of digitalis toxicity and increase frequency of serum calcium monitoring when initiating or adjusting the dose of Paricalcitol Injection in patients receiving digitalis compounds [see Warnings and Precautions (5.2) ] . Strong CYP3A Inhibitors Clinical Impact Paricalcitol Injection is partially metabolized by CYP3A. Exposure of Paricalcitol Injection will increase upon coadministration with strong CYP3A inhibitors [see Clinical Pharmacology (12.3) ] .

Examples

Clarithromycin, conivaptan, grapefruit juice, indinavir, itraconazole, ketoconazole, lopinavir/ritonavir, mibefradil, nefazodone, nelfinavir, posaconazole, ritonavir, saquinavir, and voriconazole Intervention If a patient initiates or discontinues therapy with a strong CYP3A4 inhibitor, dose adjustment of Paricalcitol Injection may be necessary. Monitor intact PTH and serum calcium concentrations closely. Strong CYP3A Inhibitors: Co-administration with strong CYP3A inhibitors (e.g., ketoconazole) increases Paricalcitol Injection exposure. Dose adjustment may be necessary. Closely monitor intact PTH and serum calcium. ( 2.4 , 7 )

Paricalcitol Injection is contraindicated in patients with: Hypercalcemia [see Warnings and Precautions (5.1) ] Vitamin D toxicity [see Warnings and Precautions (5.1) ] Known hypersensitivity to paricalcitol or any of the inactive ingredients in Paricalcitol Injection. Hypersensitivity adverse reactions have been reported [e.g., angioedema (including laryngeal edema) and urticaria] [see Adverse Reactions (6.2) ] . Hypercalcemia ( 4 ) Vitamin D toxicity ( 4 ) Known hypersensitivity to paricalcitol or any other inactive ingredient. ( 4 )

AND PRECAUTIONS Hypercalcemia : The risk may be increased when Paricalcitol Injection is used concomitantly with high dose calcium preparations, thiazide diuretics, or metabolically inactive or active forms of vitamin D. Monitor serum calcium when using Paricalcitol Injection and adjust dose accordingly. ( 5.1 )

Digitalis

Toxicity : Hypercalcemia increases the risk of digitalis toxicity. In patients using Paricalcitol Injection concomitantly with digitalis compounds, monitor both serum calcium and patients for signs and symptoms of digitalis toxicity and increase frequency of monitoring when initiating or adjusting the dose of Paricalcitol Injection. ( 5.2 ) Risk of Increased Paricalcitol Levels With Concomitant Use of Strong CYP3A Inhibitors : Use of Paricalcitol Injection with strong CYP3A inhibitors increases the concentration of paricalcitol in the blood. In patients on Paricalcitol Injection who are initiating or discontinuing drugs known to be strong CYP3A inhibitors, monitor serum calcium and PTH more frequently and adjust Paricalcitol Injection dose as required. ( 5.3 )

Adynamic Bone

Disease : May develop if PTH levels are suppressed to abnormally low levels. Monitor PTH levels and adjust Paricalcitol Injection accordingly. ( 5.4 )

5.1 Hypercalcemia Hypercalcemia may occur during Paricalcitol Injection treatment and may be exacerbated by concomitant administration of high doses of calcium containing preparations, thiazide diuretics, or vitamin D (i.e., all forms). Acute hypercalcemia may exacerbate tendencies for cardiac arrhythmias and seizures and may potentiate the effect of digitalis on the heart. Chronic hypercalcemia can lead to generalized vascular calcification and other soft-tissue calcification. Hypercalcemia may be so severe as to require emergency attention. High intake of calcium and phosphate concomitantly with vitamin D compounds may lead to hypercalcemia, hypercalciuria, and hyperphosphatemia. Prevention of such adverse reactions requires frequent serum calcium monitoring and careful Paricalcitol Injection dose adjustments. Concomitant use with other active vitamin D analogues should be avoided during Paricalcitol Injection treatment to prevent hypercalcemia. Patients also should be informed about the symptoms of elevated calcium, which include feeling tired, difficulty thinking clearly, loss of appetite, nausea, vomiting, constipation, increased thirst, increased urination and weight loss.

5.2 Digitalis Toxicity Hypercalcemia of any cause increases the risk of digitalis toxicity. In patients using Paricalcitol Injection concomitantly with digitalis compounds, monitor both serum calcium and patients for signs and symptoms of digitalis toxicity and increase frequency of monitoring when initiating or adjusting the dose of Paricalcitol Injection <span class="opacity-50 text-xs">[see Dosage and Administration ( 2 ) ]</span>.

5.3 Risk of Increased Paricalcitol Levels With Concomitant Use of Strong CYP3A Inhibitors Concomitant use of Paricalcitol Injection with strong CYP3A inhibitors will increase the levels of paricalcitol in the blood. In patients on Paricalcitol Injection who are initiating or discontinuing therapy with drugs known to be strong CYP3A inhibitors, monitor serum calcium and PTH more frequently and adjust Paricalcitol Injection dose as required <span class="opacity-50 text-xs">[see Drug Interactions ( 7.1 ), Clinical Pharmacology ( 12.3 ) ]</span>.

5.4 Adynamic Bone Disease Adynamic bone disease with subsequent increased risk of fractures may develop if PTH levels are suppressed to abnormally low levels. Monitor PTH levels and adjust Paricalcitol Injection dose <span class="opacity-50 text-xs">[see Dosage and Administration ( 2 ) ]</span>.