Promethazine

INTRODUCTION

Indications

Treatment of various allergic conditions and motion sickness. Preoperative sedation. Treatment and prevention of nausea and vomiting. Adjunct to anesthesia and analgesia.

Action

Blocks the effects of histamine. Has inhibitory effect on the chemoreceptor trigger zone in the medulla, resulting in antiemetic properties. Alters the effects of dopamine in the CNS. Possesses significant anticholinergic activity. Produces CNS depression by indirectly decreased stimulation of the CNS reticular system. Therapeutic Effects: Relief of symptoms of histamine excess usually seen in allergic conditions. Diminished nausea or vomiting. Sedation.

Adverse Reactions/Side Effects

CNS: NEUROLEPTIC MALIGNANT SYNDROME, confusion, disorientation, sedation, dizziness, extrapyramidal reactions, fatigue, insomnia, nervousness. EENT: blurred vision, diplopia, tinnitus. CV: bradycardia, hypertension, hypotension, tachycardia. GI: constipation, drug-induced hepatitis, dry mouth. Derm: photosensitivity, severe tissue necrosis upon infiltration at IV site, rashes. Hemat: blood dyscrasias.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Monitor and report signs of neuroleptic malignant syndrome, including hyperthermia, diaphoresis, generalized muscle rigidity, altered mental status, tachycardia, changes in blood pressure (BP), and incontinence. Symptoms typically occur within 4–14 days after initiation of drug therapy, but can occur at any time during drug use.

• Assess motor function, and be alert for extrapyramidal reactions. Report these symptoms immediately, especially tardive dyskinesia, because this problem may be irreversible. Common extrapyramidal symptoms include:

  • ∘ Tardive dyskinesia (uncontrolled rhythmic movement of mouth, face, and extremities, lip smacking or puckering, puffing of cheeks, uncontrolled chewing, rapid or worm-like movements of tongue).

  • ∘ Pseudoparkinsonism (shuffling gait, rigidity, tremor, pill-rolling motion, loss of balance control, difficulty speaking or swallowing, mask-like face).

  • ∘ Akathisia (restlessness or desire to keep moving).

  • ∘ Other dystonias and dyskinesias (dystonic muscle spasms, twisting motions, twitching, inability to move eyes, weakness of arms or legs).

• Assess heart rate, ECG, and heart sounds, especially during exercise (See Appendices G, H). Report any rhythm disturbances or symptoms of increased arrhythmias, including palpitations, chest discomfort, shortness of breath, fainting, and fatigue/weakness.

• Assess 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).

• Monitor unusual weakness and fatigue that might be due to anemia or other symptoms such as fever, sore throat, mucosal lesions, or signs of infection that might be due to other blood dyscrasias. Notify physician if these signs occur.

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

• Monitor changes in mood and behavior, ...