Dantrolene

INTRODUCTION

Indications

PO: Treatment of spasticity associated with Spinal cord injury, Stroke, Cerebral palsy, Multiple sclerosis. Prophylaxis of malignant hyperthermia. IV: Emergency treatment of malignant hyperthermia. Unlabeled Use: Management of neuroleptic malignant syndrome.

Action

Acts directly on skeletal muscle, causing relaxation by decreasing calcium release from sarcoplasmic reticulum in muscle cells. Prevents intense catabolic process associated with malignant hyperthermia. Therapeutic Effects: Reduction of muscle spasticity. Prevention of malignant hyperthermia.

Adverse Reactions/Side Effects

CNS: drowsiness, muscle weakness, confusion, dizziness, headache, insomnia, malaise, nervousness. EENT: excessive lacrimation, visual disturbances. Resp: pleural effusions. CV: changes in blood pressure, tachycardia. GI: HEPATOTOXICITY, diarrhea, anorexia, cramps, dysphagia, GI bleeding, vomiting. GU: crystalluria, dysuria, frequency, erectile dysfunction, incontinence, nocturia. Derm: pruritus, sweating, urticaria. Hemat: eosinophilia. Local: irritation at IV site, phlebitis. MS: myalgia. Misc: chills, drooling, fever.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Be alert for signs of hepatotoxicity, including anorexia, abdominal pain, severe nausea and vomiting, yellow skin or eyes, fever, sore throat, malaise, weakness, facial edema, lethargy, and unusual bleeding or bruising. Report these signs to the physician immediately.

• Assess patient's spasticity, ROM, functional ability, and posture (e.g., head control and trunk stability), especially when beginning Dantrium treatment or during dose adjustments. Communicate with physician, family/caregivers, and other health professionals to determine if dosage is helping achieve desired functional outcomes.

• Assess dizziness or drowsiness that might affect gait, balance, and other functional activities (See Appendix C). Report balance problems and functional limitations to the physician, and caution the patient and family/caregivers to guard against falls and trauma.

• Monitor symptoms such as confusion, nervousness, insomnia, or malaise. Report these problems; excessive or prolonged CNS symptoms may require a reduction in dose.

• Monitor signs of eosinophilia such as fatigue, weakness, and muscle pain (myalgia); report these signs to the physician.

• Assess blood pressure (BP) and compare to normal values (See Appendix F). Report changes in BP, either a problematic decrease in BP (hypotension) or a sustained increase in BP (hypertension).

• Assess heart rate, ECG, and heart sounds, especially during exercise (see Appendixes G, H). Report a rapid heart rate (tachycardia) or symptoms of other arrhythmias, including palpitations, chest discomfort, shortness of breath, fainting, and fatigue/weakness.

• Assess any breathing problems or signs of pleural effusion, including shortness of breath, chest pain, cough, and labored breathing. Monitor pulse oximetry and perform pulmonary function tests (See Appendices I, J, K) to quantify suspected changes in ventilation and respiratory function.

• Assess injection site during and after IV administration, and report signs of phlebitis (local pain, swelling, inflammation).

Interventions

• Implement aggressive therapeutic exercises (neuromuscular reeducation, postural stabilization, gait ...