Lysodren

mitotane

(mye-toe-tane) mitotane,

o,p′-DDD

(trade name),

Lysodren

(trade name)

Classification

Therapeutic: antineoplastics
Pregnancy Category: C

Indications

Inoperable carcinoma of the adrenal cortex.Cushing’s syndrome due to pituitary disorders.

Action

Suppresses adrenal function.Has a direct cytotoxic effect on adrenal tumors.Structurally related to DDT (an insecticide).

Therapeutic effects

Regression of adrenal cortical tumors.

Pharmacokinetics

Absorption: 30–40% absorbed following oral administration.Distribution: Widely distributed to all body tissues; accumulates in fatty tissue.Metabolism and Excretion: Slowly released from fatty tissue. Mostly metabolized by the liver; 10% excreted by the kidneys; 15% excreted in bile.Half-life: 18–159 days.

Time/action profile (clinical effects†)

ROUTEONSETPEAKDURATION
PO2–4 wk6 wkunknown
†Onset = inhibition of adrenocortical function; peak = tumor response

Contraindications/Precautions

Contraindicated in: Hypersensitivity.Use Cautiously in: Obesity (↑ risk of adverse reactions); Obstetric / Lactation / Pediatric: Pregnancy, lactation, or children (especially first trimester of pregnancy; safety not established).Exercise Extreme Caution in: Shock or severe trauma; discontinue temporarily and administer steroids.

Adverse Reactions/Side Effects

Central nervous system

  • lethargy (most frequent)
  • somnolence (most frequent)
  • brain damage
  • dizziness
  • fatigue
  • functional impairment (high-dose, long-term therapy)
  • headache
  • irritability
  • mental depression
  • tremors
  • vertigo
  • weakness

Ear, Eye, Nose, Throat

  • blurred vision
  • ↓ hearing
  • diplopia
  • lens opacities
  • optic neuritis
  • toxic retinopathy

Respiratory

  • shortness of breath
  • wheezing

Cardiovascular

  • hypertension
  • hypotension

Gastrointestinal

  • anorexia (most frequent)
  • diarrhea (most frequent)
  • nausea (most frequent)
  • vomiting (most frequent)
  • ↑ salivation

Genitourinary

  • albuminuria
  • hematuria
  • hemorrhagic cystitis

Dermatologic

  • maculopapular rash (most frequent)
  • flushing

Endocrinologic

  • adrenal suppression (most frequent)
  • gynecomastia

Metabolic

  • hypercholesterolemia (most frequent)
  • hypouricemia (most frequent)

Musculoskeletal

  • aching
  • arthralgia
  • myalgia

Miscellaneous

  • fever

Interactions

Drug-Drug interaction

Stimulates hepatic drug-metabolizing enzymes, which may ↓ the effectiveness of drugs that are highly metabolized (warfarin, phenytoin ).Additive CNS depression with other CNS depressants, includingalcohol, antihistamines, antidepressants, opioid analgesics, or sedative/hypnotics.Spironolactone may block the effects of mitotane in Cushing’s disease.

Route/Dosage

Adrenocortical CarcinomaOral (Adults) 2–6 g/day in 3–4 divided doses; may be ↑ as tolerated (range 2–16 g/day).Cushing’s SyndromeOral (Adults) 3–6 g/day in 3–4 divided doses initially, ↓ to maintenance dose of 500 mg twice weekly to 2 g/day (unlabeled use).

Availability

Tablets: 500 mg

Nursing implications

Nursing assessment

  • Monitor for symptoms of adrenal insufficiency (anorexia, nausea and vomiting, diarrhea, fatigue, weakness, hypotension, darkening of skin). Obese patients are at increased risk for this side effect.
  • Monitor for development of dose-limiting side effects (severe nausea, vomiting, anorexia, or diarrhea). Antiemetics may be needed. Adjust diet as tolerated to maintain nutritional intake and fluid and electrolyte balance.
  • Monitor neurologic status; report depression, lethargy, and complaints of dizziness.
  • Lab Test Considerations: 8-hr plasma cortisol concentrations and 24-hr urine tests for 17-hydroxycorticosteroid concentrations should be obtained prior to and periodically throughout therapy to determine degree of adrenal suppression. May be decreased because of adrenocortical inhibition.
    • May decrease serum uric acid and protein-bound iodine (PBI) concentrations.

Potential Nursing Diagnoses

Deficient knowledge, related to medication regimen (Patient/Family Teaching)

Implementation

  • Treatment should be instituted in the hospital until a stable dose regimen is achieved.
  • Wear gloves when handling bottles of mitotane.
  • Oral: Premedication with an antiemetic may be necessary. Swallow tablets whole; do not break or crush.

Patient/Family Teaching

  • Instruct patient to take medication exactly as directed. Take missed doses as soon as remembered unless almost time for next dose. Notify health care professional of missed doses.
  • Explain to patient that this drug suppresses the adrenal glands and therefore impairs the body’s ability to cope with stress. Concurrent corticosteroid and mineralocorticoid therapy may be ordered to ensure that adequate amounts of adrenal hormones are present. Health care professional should be notified if an infection, illness, or injury occurs because supplemental steroids may be necessary or mitotane may need to be discontinued in the event of severe trauma or shock.
  • May cause drowsiness. Caution patient to avoid driving or other activities requiring alertness until response to medication is known.
  • Instruct patient to notify health care professional if depression, nausea, vomiting, anorexia, diarrhea, skin rash, or darkening of skin occurs or if muscle aches, fever, flushing, or muscle twitching becomes pronounced.
  • Caution patient to avoid taking alcohol or other CNS depressants with this medication.
  • Advise patient to use a nonhormonal form of contraception throughout therapy.
  • Advise patient to carry identification describing medication regimen in the event of an emergency in which patient cannot relate medical history.
  • Explain need for continued medical follow-up, including neurologic exam to assess effectiveness and possible side effects of medication.

Evaluation/Desired Outcomes

  • Reduction in tumor mass.
    • Slowing of growth of metastatic lesions.
    • Decreased pain, weakness, anorexia, and steroid symptoms. May require >3 mo at the maximum tolerated dose for a measurable response.