hyoscyamine

IM:

BEERS REMS

Control of gastric secretion, visceral spasm, hypermotility in spastic colitis, spastic bladder, pylorospasm, and related abdominal cramps.
Decreases symptoms of various functional intestinal disorders including mild dysenteries, diverticulitis, infant colic, biliary and renal colic.
Adjunctive therapy in peptic ulcer disease, irritable bowel syndrome, neurogenic bowel disturbances.
Decreases pain and hypersecretion associated with pancreatitis.
Relief of symptoms of acute rhinitis.
Decreases rigidity and tremors associated with parkinsonism and controls related sialorrhea and hyperhidrosis. May also be used to manage anticholinesterase poisoning.
Management of cystitis or renal colic.
Management of some forms of heart block due to vagal activity.
IV: SC: Facilitation of diagnostic hypotonic duodenography; may also increase radiologic visibility of the kidneys.
Preoperative administration decreases secretions and blocks bradycardia associated with some forms of anesthesia and related surgical agents.

Action ⬆ ⬇

Inhibits the muscarinic effect of acetylcholine in smooth muscle, secretory glands and the CNS. Small doses decrease salivary and bronchial secretions and decrease sweating; intermediate doses dilate the pupil, inhibit accommodation, increase heart rate (vagolytic action); large doses decrease GI and GU motility, further increase in dose decreases gastric acid secretion.

Therapeutic effects:

Decreased secretions with decreased GI and GU symptomatology.
Increased heart rate.

Pharmacokinetics ⬆ ⬇

Absorption: Well absorbed.

Distribution: Crosses the blood-brain barrier.

Metabolism/Excretion: Excreted mostly unchanged by the kidneys.

Half-Life: 3.5 hr.

Time/Action Profile ⬆ ⬇

(GI effects)

ROUTE	ONSET	PEAK	DURATION
PO	20–30 min	unknown	4–6 hr
IM, IV, SUBQ	2–3 min	unknown	4–6 hr

Contraind./Precautions ⬆ ⬇

Contraindicated in:

Hypersensitivity;
Angle-closure glaucoma;
Tachycardia or unstable cardiovascular status;
GI obstructive disease, paralytic ileus, intestinal atony, severe ulcerative colitis;
Obstructive uropathy;
Myasthenia gravis;
Some products contain alcohol, sulfites, or tartrazine and should be avoided in patients with known intolerance/hypersensitivity.
Lactation: Lactation;
Pedi: Products containing benzyl alcohol should not be used in newborn or immature infants.

Use Cautiously in:

History of cardiovascular disease including HF, arrhythmias, hypertension, tachycardia, or coronary artery disease;
Renal impairment;
Hepatic impairment;
Prostatic hyperplasia;
Early ileus or reflux esophagitis;
Automonic neuropathy;
Hyperthyroidism;
Pedi: Infants, small children, Down syndrome, brain damage, or spastic paralysis ( sensitivity);
OB: May cause fetal tachycardia; safety not established;
Geri: Appears on Beers list. risk of adverse reactions in older adults due to anticholinergic effects. Avoid use in older adults.

Adv. Reactions/Side Effects ⬆ ⬇

CV: palpitations, tachycardia

Derm: ↓sweating, urticaria

EENT: blurred vision, cycloplegia, ↑intraocular pressure, mydriasis, photophobia

Endo: suppression of lactation

GI: nausea, dry mouth, altered taste perception, bloated feeling, constipation, paralytic ileus, vomiting

GU: erectile dysfunction, urinary hesitancy/retention

Local: local irritation (IM, IV, SUBQ)

Neuro: confusion/excitement (especially in geriatric patients), dizziness, flushing, headache, insomnia, light-headedness (IM, IV, SUBQ), nervousness

Misc: fever (especially in children), HYPERSENSITIVITY REACTIONS (INCLUDING ANAPHYLAXIS)

Interactions ⬆ ⬇

Drug-drug:

Concurrent administration with amantadine↑ anticholinergic side effects (may require dose ↓).
↑effects of atenolol.
Concurrent use with phenothiazines may result in ↓ effect of phenothiazine and ↑ anticholinergic side effects (dose reduction may be necessary).
↑anticholinergic side effects with tricyclicantidepressants.

Route/Dosage ⬆ ⬇

PO
(Adults ): 0.125–0.25 mg 3–4 times daily or 0.375–0.75 mg as sustained release form every 12 hr.
PO (Children 34–36 kg): 125–187 mcg every 4 hr as needed.
PO (Children 22.7–33 kg): 94–125 mcg every 4 hr as needed.
PO (Children 13.6–22.6 kg): 63 mcg every 4 hr as needed.
PO (Children 9.1–13.5 kg): 31.3 mcg every 4 hr as needed.
PO (Children 6.8–9 kg): 25 mcg every 4 hr as needed.
PO (Children 4.5–6.7 kg): 18.8 mcg every 4 hr as needed.
PO (Children 3.4–4.4 kg): 15.6 mcg every 4 hr as needed.
PO (Children 2.3–3.3 kg): 12.5 mcg every 4 hr as needed.
IM IV SC (Adults ): Gastrointestinal anticholinergic: 0.25–0.5 mg 3–4 times daily as needed; preoperative prophylaxis of secretions: 0.5 mg or 0.005 mg/kg 30–60 min before anesthesia; antiarrhythmic: 0.125 mg IV repeated as needed; cholinergic adjunct (curariform block): 0.2 mg for each 1 mg of neostigmine.
IM IV SC (Children ≥2 yr): Preoperative prophylaxis of secretions: 0.005 mg/kg 30–60 min before anesthesia.

Availability ⬆ ⬇

(Generic available)

Tablets: 0.125 mg
Sublingual tablets: 0.125 mg
Chewable tabletsmint: 0.125 mg
Orally disintegrating tabletsmint: 0.125 mg
Extended-release tablets: 0.375 mg
Solution (drops)orange: 0.125 mg/mL
Elixirorange: 0.125 mg/5 mL
Injection: 0.5 mg/mL

Assessment ⬆ ⬇

Assess vital signs and ECG tracings frequently during IV drug therapy. Report any significant changes in heart rate or BP, or increased ventricular ectopy or angina promptly.
- Monitor intake and output ratios in elderly or surgical patients because hyoscyamine may cause urinary retention.
- Assess patients routinely for abdominal distention and auscultate for bowel sounds. If constipation becomes a problem, increasing fluids and adding bulk to the diet may help alleviate constipation.

Implementation ⬆ ⬇

Do not confuse Levbid with Enbrel.
PO: Oral doses are usually given 30 min before meals. Swallow extended-release and time-release products whole; do not open, break, crush, or chew.
- Antacids may interfere with absorption. Administer hyosyamine before meals and antacids after meals.
- ODT: Place tablet on tongue and allow the tablet to disintegrate before swallowing; may take with or without water.
- SL
  May be taken orally or chewed.

IV Administration:

Diluent: May give IV undiluted or dilute in 10 mL of sterile water.

Patient/Family Teaching ⬆ ⬇

Instruct patient to take exactly as directed. Take missed doses as soon as remembered unless almost time for next dose. Do not double doses.
- May cause drowsiness. Caution patients to avoid driving or other activities requiring alertness until response to medication is known.
- Instruct patient that oral rinses, sugarless gum or candy, and frequent oral hygiene may help relieve dry mouth.
- Caution patients that hyoscyamine impairs heat regulation. Strenuous activity in a hot environment may cause heat stroke.
- Advise patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and to consult with health care professional before taking other medications.
- Inform male patients with benign prostatic hyperplasia that hyoscyamine may cause urinary hesitancy and retention. Changes in urinary stream should be reported to health care professional.
- Advise females of reproductive potential to notify health care professional if pregnancy is planned or suspected and to avoid breastfeeding during therapy.

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Pronunciation ⬇

Classifications ⬆ ⬇

Indications ⬆ ⬇