SCOPOLAMINE
(skoe-pol'a-meen)
Transderm-Scop, Transderm-V

SCOPOLAMINE HYDROBROMIDE
Hyoscine, Isopto-Hyoscine, Murocoll, Triptone
Classifications: autonomic nervous system agent; anticholinergic (parasympatholytic); antimuscarinic; antispasmodic
Prototype: Atropine
Pregnancy Category: C

Availability

Scopolamine 0.4 mg tablets; 1.5 mg transdermal patch

Scopolamine HBr 0.4 mg tablets; 0.3 mg/mL, 0.4 mg/mL, 0.86 mg/mL, 1 mg/mL injection; 0.25% ophthalmic solution

Actions

Alkaloid of belladonna with peripheral actions resembling those of atropine. In contrast to atropine, produces CNS depression with marked sedative and tranquilizing effects, and is less effective in preventing reflex bradycardia during anesthesia. More potent in mydriatic and cycloplegic actions and in inhibiting secretions of salivary, bronchial, and sweat glands, but has less prominent effect on heart, intestines, and bronchial muscles.

Therapeutic Effects

More potent than atropine in mydriatic and cycloplegic actions. Produces CNS depression with marked sedative and tranquilizing effects for use in anesthesia. Used as a preanesthetic agent to control bronchial, nasal, pharyngeal and salivary secretions.

Uses

In obstetrics with morphine to produce amnesia and sedation ("twilight sleep") and as preanesthetic medication. To control spasticity (and drooling) in postencephalitic parkinsonism, paralysis agitans, and other spastic states, as prophylactic agent for motion sickness and as mydriatic and cycloplegic in ophthalmology. Therapeutic system (Transderm-Scop) is used to prevent nausea and vomiting associated with motion sickness.

Contraindications

Asthma; hepatitis; toxemia of pregnancy; hypersensitivity to anticholinergic drugs; hypersensitive to belladonna or barbiturates; narrow angle glaucoma; GI or urogenital obstructive diseases; myasthenia gravis; pregnancy (category C), lactation.

Cautious Use

Coronary heart disease, CHF, cardiac arrhythmias, tachycardia, hypertension; patients over 40 y, pyloric obstruction, urinary bladder neck obstruction, angle-closure glaucoma, thyrotoxicosis, liver disease; paralytic ileus; hiatal hernia, ulcerative colitis, gastric ulcer; older adults, parkinsonism; COPD, asthma or allergies; hyperthyroidism; brain damage, spastic paralysis; tartrazine or sulfite sensitivity.

Route & Dosage

Preanesthetic
Adult: PO 0.5–1 mg IM/SC/IV 0.3–0.6 mg
Child: PO/IM/SC/IV 0.006 mg/kg

Motion Sickness
Adult: PO 0.25–0.6 mg 1 h before anticipated travel Topical 1 patch q72h starting 12 h before anticipated travel
Child: PO 0.006 mg/kg 1 h before anticipated travel

Refraction
Adult: Ophthalmic 1–2 drops in eye 1 h before refraction

Uveitis
Adult: Ophthalmic 1–2 drops in eye up to q.i.d.

Administration

Instillation

Minimize possibility of systemic absorption by applying pressure against lacrimal sac during and for 1 or 2 min following instillation of eye drops.

Transdermal

Apply transdermal disc system (Transderm-Scop, a Controlled-Release System) to dry surface behind the ear.
Replace with another disc on another site behind the ear if disc system becomes dislodged.

Subcutaneous or/Intramuscular

Give undiluted.

Intravenous

PREPARE: Direct: Dilute required dose in 10 mL of sterile water for injection.

ADMINISTER: Direct: Give a single dose over 1 min.

Preserve in tight, light-resistant containers.

Adverse Effects (1%)

Body as a Whole: Fatigue, dizziness, drowsiness, disorientation, restlessness, hallucinations, toxic psychosis. GI: Dry mouth and throat, constipation. Urogenital: Urinary retention. CV: Decreased heart rate. Special Senses: Dilated pupils, photophobia, blurred vision, local irritation, follicular conjunctivitis. Respiratory: Depressed respiration. Skin: Local irritation from patch adhesive, rash.

Interactions

Drug: Amantadine, antihistamines, tricyclic antidepressants, quinidine, disopyramide, procainamide add to anticholinergic effects; decreases levodopa effects; methotrimeprazine may precipitate extrapyramidal effects; decreases antipsychotic effects (decreased absorption) of phenothiazines.

Pharmacokinetics

Absorption: Readily absorbed from GI tract and percutaneously. Peak: 20–60 min. Duration: 5–7 d. Distribution: Crosses placenta; distributed to CNS. Metabolism: Metabolized in liver. Elimination: Excreted in urine.

Nursing Implications

Assessment & Drug Effects

Observe patient closely; some patients manifest excitement, delirium, and disorientation shortly after drug is administered until sedative effect takes hold.
Use of side rails is advisable, particularly for older adults, because of amnesic effect of scopolamine.
In the presence of pain, scopolamine may cause delirium, restlessness, and excitement unless given with an analgesic.
Be aware that tolerance may develop with prolonged use.
Terminate ophthalmic use if local irritation, edema, or conjunctivitis occur.

Patient & Family Education

Vision may blur when used as mydriatic or cycloplegic; do not drive or engage in potentially hazardous activities until vision clears.
Place disc on skin site the night before an expected trip or anticipated motion for best therapeutic effect.
Wash hands carefully after handling scopolamine. Anisocoria (unequal size of pupils, blurred vision can develop by rubbing eye with drug-contaminated finger).

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug