PLICAMYCIN
(plik-a-mi'cin)
Mithracin, Mithramycin
Classifications: antineoplastic; antibiotic
Prototype: Doxorubicin
Pregnancy Category: C
|
2500 mcg injection
Cytotoxic antibiotic produced by Streptomyces plicatus, with minimal immunosuppressive activity. Complexes with DNA, thus inhibiting DNA-directed RNA synthesis.
May lower serum calcium levels by unclear mechanism. Appears to block hypercalcemic action of vitamin D, and may inhibit parathyroid
hormone effect on osteoclasts. Interferes with synthesis of various clotting factors. High toxicity with low therapeutic index
limits clinical use.
To treat hospitalized patients with hypercalcemia or hypercalciuria associated with advanced neoplasms and to treat testicular
malignancy.
Bleeding and coagulation disorders, myelosuppression; electrolyte imbalance (especially hypocalcemia, hypokalemia, hypophosphatemia);
pregnancy (category C), lactation.
Patients with prior abdominal or mediastinal radiology; liver or renal impairment.
Neoplasia
Adult: IV 25–30 mcg/kg once/d for 8–10 d or until toxicity necessitates discontinuing (max: 30 mcg/kg/d for 10 d)
Malignant Hypercalcemia
Adult: IV 25 mcg/kg once/d for 3–4 d, may repeat after 1 wk
|
Intravenous
- Base drug dose on ideal body weight when edema, ascites, or hydrothorax is present.
PREPARE: IV Infusion: Dilute each 2.5 mg with 4.9 mL of sterile water to yield 500 mcg/mL. Withdraw the calculated dose and further dilute in 1000
mL of D5W or D5/NS.
ADMINISTER: IV Infusion: Give at a rate of 4–6 h per liter. Regulate IV flow rate carefully (established by physician); GI adverse effects increase
when rate is too fast. Terminate infusion immediately if extravasation occurs. Apply moderate heat to disperse the drug and
to minimize tissue irritation.
INCOMPATIBILITIES Y-site:
Cefepime.
|
- Discard unused portions of reconstituted solution and prepare new ones daily.
- Refrigerate unreconstituted vials at 2°–8° C (36°–46° F).
CNS: Drowsiness, irritability, dizziness, weakness, headache, mental depression. GI:
Stomatitis, anorexia, nausea, vomiting, diarrhea, widespread intestinal hemorrhage. Hematologic: Thrombocytopenia, bleeding and coagulation disorders (dose related), leukopenia (mild). Body as a Whole: Fever, marked facial flushing, hemoptysis, abnormal liver and renal function tests. Skin: Nonspecific or acneiform skin rash, phlebitis. Metabolic: Hypophosphatemia, hypokalemia, hypocalciuria.
Drug: Concomitant administration of vitamin D may enhance hypercalcemia.
Distribution: Crosses blood–brain barrier; appears to localize in areas of bone active resorption. Elimination: Excreted in urine.
Assessment & Drug Effects
-
Note: Therapy is usually interrupted if leukocyte count is <4000/mm3, if platelet count is <150,000/mm3, or if PT is >4 sec higher than control (normal: 12–14 sec).
- Establish flow chart at beginning of therapy, permitting continuous record of weight and I&O ratio and pattern.
- Lab tests: Perform frequent assessments of liver and hematologic (platelet count, bleeding and prothrombin times) and kidney
function throughout therapy and for several days after last dose; periodic serum electrolytes.
- Report marked facial flushing. It is often an early symptom or thrombocytopenia, which frequently is evidenced by a single
or persistent episode of epistaxis or hematemesis; may be rapid in onset during or after a course of treatment.
- Inspect skin daily for signs of purpura. Report hemoptysis immediately, which may occur because of bleeding into metastasis.
-
Note: Rebound hypercalcemia (normal: 9–10.6 mg/dL) following plicamycin-induced hypocalcemia may persist 2–4 d (see Appendix
F).
- Monitor I&O ratio to assure adequate fluid intake; the hypercalcemia patient may be dehydrated.
- Monitor for S&S of adverse effects on the GI mucosal cells (hematemesis, melena) that will necessitate stopping drug use.
- Check patient's bowel function daily to prevent high fecal impaction due to diminished peristalsis.
- Consult physician about dietary calcium intake and coordinate dietary planning with dietitian, patient, and family.
Patient & Family Education
- Use a reliable form of birth control during and for several months following completion of treatment with plicamycin.
- Report easy bruising or bleeding immediately to your physician.
1%)
Canadian drug name; 
Prototype drug