Hyoscyamine 0.5mg/ml Inj, 1ml
It is used to slow the speed in the stomach and GI (gastrointestinal) tract.It is used to treat diarrhea.It is used to treat GI (gastrointestinal) ulcers.It is used to treat irritable bowel syndrome.It is used to treat muscle spasms of the GI (gastrointestinal) tract, gallbladder system, or urinary system.It is used to treat a runny nose.It is used to treat Parkinson's disease.It is used to prevent irritation of the pancreas.It is used during surgery.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Anticholinergic; Antispasmodic
Pharmacologic Class
Muscarinic Acetylcholine Receptor Antagonist
Pregnancy Category
Category C
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
Hyoscyamine injection is a medication used to treat various stomach and intestinal problems, such as cramps, spasms, and excessive secretions. It works by relaxing the muscles in your digestive system and reducing the amount of fluids your body produces. It can also be used before surgery to reduce saliva and other secretions.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided to you. It is essential to follow the instructions carefully. This medication is administered via injection into a muscle, vein, or the fatty layer under the skin.
Storing and Disposing of Your Medication
If you need to store this medication at home, consult with your doctor, nurse, or pharmacist to determine the proper storage method.
Missing a Dose
If you miss a dose, contact your doctor to receive guidance on what to do next.
To use this medication correctly, follow your doctor's instructions and read all the information provided to you. It is essential to follow the instructions carefully. This medication is administered via injection into a muscle, vein, or the fatty layer under the skin.
Storing and Disposing of Your Medication
If you need to store this medication at home, consult with your doctor, nurse, or pharmacist to determine the proper storage method.
Missing a Dose
If you miss a dose, contact your doctor to receive guidance on what to do next.
Lifestyle & Tips
- Avoid activities requiring mental alertness or coordination until you know how the medication affects you, as it can cause dizziness or blurred vision.
- Avoid overheating and stay hydrated, especially in hot weather or during exercise, as this medication can decrease sweating and increase body temperature.
- Report any difficulty urinating or severe constipation to your healthcare provider.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
0.25 to 0.5 mg (0.5 to 1 mL) IM, IV, or SC every 4 to 6 hours as needed.
Dose Range:
0.25 - 0.5 mg
Condition-Specific Dosing:
preoperative:
0.25 to 0.5 mg IM, IV, or SC 30 to 60 minutes prior to anesthesia to reduce secretions and prevent bradycardia.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established for injection; oral forms are used with weight-based dosing. If parenteral use is considered, dose must be carefully individualized and is typically lower than adult doses, based on weight and clinical response.
Adolescent:
Typically adult dosing (0.25 to 0.5 mg IM, IV, or SC every 4 to 6 hours as needed), but individualized based on weight and response.
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment recommended, but monitor for increased anticholinergic effects.
Moderate:
Use with caution; consider lower doses and extended dosing intervals due to potential for accumulation and increased sensitivity to anticholinergic effects. Monitor closely.
Severe:
Use with extreme caution or avoid. Significant risk of accumulation and severe anticholinergic adverse effects. Monitor closely for CNS and peripheral anticholinergic toxicity.
Dialysis:
Not well-studied; likely not dialyzable. Use with extreme caution or avoid.
Hepatic Impairment:
Mild:
No specific adjustment recommended.
Moderate:
Use with caution; monitor for increased anticholinergic effects as metabolism may be impaired.
Severe:
Use with caution; consider lower doses and extended dosing intervals. Monitor closely for CNS and peripheral anticholinergic toxicity.
Pharmacology
Mechanism of Action
Hyoscyamine is a belladonna alkaloid that acts as a non-selective antagonist of muscarinic acetylcholine receptors. It competitively blocks the action of acetylcholine at postganglionic parasympathetic neuroeffector sites, leading to a reduction in gastrointestinal motility and secretions, relaxation of smooth muscle, and effects on the heart, salivary glands, and eyes.
Pharmacokinetics
Absorption:
Bioavailability:
Approximately 100% (for IM/IV/SC administration)
Tmax:
IM/SC: 30-60 minutes; IV: Immediate
FoodEffect:
Not applicable for injection
Distribution:
Vd:
Approximately 2-4 L/kg
ProteinBinding:
Approximately 50%
CnssPenetration:
Yes (crosses blood-brain barrier, can cause CNS effects)
Elimination:
HalfLife:
Approximately 3.5 hours
Clearance:
Not precisely quantified, primarily renal excretion
ExcretionRoute:
Renal (urine)
Unchanged:
Approximately 13-50%
Pharmacodynamics
OnsetOfAction:
IV: Immediate; IM/SC: 5-15 minutes
PeakEffect:
30-60 minutes
DurationOfAction:
4-6 hours
Safety & Warnings
Side Effects
Serious Side Effects: Seek Medical Help Immediately
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you experience any of the following symptoms, contact your doctor or seek medical attention right away:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
Diarrhea
Confusion
Mood changes
Changes in behavior
Hallucinations (seeing or hearing things that are not there)
Memory problems or loss
Trouble sleeping
Changes in speech
Changes in balance
Changes in eyesight, eye pain, or severe eye irritation
Difficulty urinating
Inability to sweat during physical activity or in warm temperatures
Fever
Flushing
Fast or abnormal heartbeat
Erectile dysfunction
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Dizziness
Drowsiness
Fatigue
Weakness
Blurred vision
Constipation
Dry mouth
Dry eyes
Headache
Nausea or vomiting
Stomach pain
Changes in taste
Nervousness or excitability
Feeling full
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you experience any of the following symptoms, contact your doctor or seek medical attention right away:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
Diarrhea
Confusion
Mood changes
Changes in behavior
Hallucinations (seeing or hearing things that are not there)
Memory problems or loss
Trouble sleeping
Changes in speech
Changes in balance
Changes in eyesight, eye pain, or severe eye irritation
Difficulty urinating
Inability to sweat during physical activity or in warm temperatures
Fever
Flushing
Fast or abnormal heartbeat
Erectile dysfunction
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Dizziness
Drowsiness
Fatigue
Weakness
Blurred vision
Constipation
Dry mouth
Dry eyes
Headache
Nausea or vomiting
Stomach pain
Changes in taste
Nervousness or excitability
Feeling full
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe dry mouth that interferes with speaking or swallowing
- Inability to urinate or significant difficulty urinating
- Severe constipation or abdominal pain
- Blurred vision, eye pain, or sensitivity to light
- Fast or irregular heartbeat (palpitations)
- Confusion, disorientation, hallucinations, or unusual excitement
- Dizziness or lightheadedness
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain health conditions, including:
+ Bowel blockage
+ Bleeding problems
+ Diarrhea
+ Enlarged colon
+ Glaucoma
+ Heart problems
+ Myasthenia gravis
+ Slow-moving gastrointestinal (GI) tract
+ Abnormalities of the esophagus
+ Ulcerative colitis
+ Difficulty urinating
This list is not exhaustive, and it is crucial to discuss all your health problems with your doctor.
Additionally, provide your doctor and pharmacist with a comprehensive list of all the medications you are taking, including:
Prescription medications
Over-the-counter (OTC) medications
Natural products
Vitamins
It is vital to verify that it is safe to take this medication with all your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain health conditions, including:
+ Bowel blockage
+ Bleeding problems
+ Diarrhea
+ Enlarged colon
+ Glaucoma
+ Heart problems
+ Myasthenia gravis
+ Slow-moving gastrointestinal (GI) tract
+ Abnormalities of the esophagus
+ Ulcerative colitis
+ Difficulty urinating
This list is not exhaustive, and it is crucial to discuss all your health problems with your doctor.
Additionally, provide your doctor and pharmacist with a comprehensive list of all the medications you are taking, including:
Prescription medications
Over-the-counter (OTC) medications
Natural products
Vitamins
It is vital to verify that it is safe to take this medication with all your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
Before operating a vehicle or engaging in any activity that requires alertness and clear vision, ensure you understand how this medication affects you.
Consult your doctor before consuming alcohol, using marijuana or other cannabis products, or taking prescription or over-the-counter medications that may impair your reactions.
There is a risk of heat stroke associated with this medication, especially in hot weather or during physical activity. Exercise caution and stay hydrated.
To manage dry mouth, practice good oral hygiene, and consider sucking on hard, sugar-free candy or chewing sugar-free gum. Regular dental check-ups are also recommended.
If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects.
Note that different brands of this medication may be suitable for children of varying ages. Before administering this medication to a child, consult with their doctor.
When giving this medication to a child, exercise caution, as the risk of certain side effects may be higher in pediatric patients.
If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor. It is crucial to discuss the potential benefits and risks of this medication to both you and your baby.
Before operating a vehicle or engaging in any activity that requires alertness and clear vision, ensure you understand how this medication affects you.
Consult your doctor before consuming alcohol, using marijuana or other cannabis products, or taking prescription or over-the-counter medications that may impair your reactions.
There is a risk of heat stroke associated with this medication, especially in hot weather or during physical activity. Exercise caution and stay hydrated.
To manage dry mouth, practice good oral hygiene, and consider sucking on hard, sugar-free candy or chewing sugar-free gum. Regular dental check-ups are also recommended.
If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects.
Note that different brands of this medication may be suitable for children of varying ages. Before administering this medication to a child, consult with their doctor.
When giving this medication to a child, exercise caution, as the risk of certain side effects may be higher in pediatric patients.
If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor. It is crucial to discuss the potential benefits and risks of this medication to both you and your baby.
Overdose Information
Overdose Symptoms:
- Exaggerated anticholinergic effects: severe dry mouth, dilated pupils (mydriasis), blurred vision, flushed hot skin, fever, tachycardia, hypertension followed by hypotension, urinary retention, decreased bowel sounds, abdominal distention.
- CNS effects: restlessness, tremor, ataxia, dizziness, headache, delirium, hallucinations, convulsions, coma.
- Severe cases: respiratory depression, circulatory collapse, paralysis.
What to Do:
Seek immediate medical attention. Call 911 or Poison Control (1-800-222-1222). Treatment is supportive and may include physostigmine (an acetylcholinesterase inhibitor) to reverse anticholinergic effects, gastric lavage (if oral overdose), activated charcoal, and symptomatic treatment for fever, seizures, or cardiovascular instability.
Drug Interactions
Major Interactions
- Potassium chloride (solid oral dosage forms): Increased risk of GI lesions due to decreased GI motility.
- Other anticholinergics (e.g., atropine, scopolamine, dicyclomine, tricyclic antidepressants, phenothiazines, antihistamines, quinidine, disopyramide): Potentiation of anticholinergic effects (e.g., dry mouth, blurred vision, urinary retention, constipation, CNS effects).
Moderate Interactions
- Antacids: May decrease absorption of oral hyoscyamine (not directly relevant for injection, but general caution).
- Drugs that affect GI motility (e.g., metoclopramide, prokinetic agents): Antagonistic effects.
- Opioid analgesics: Increased risk of severe constipation and paralytic ileus due to additive effects on GI motility.
Monitoring
Baseline Monitoring
Vital Signs (Heart Rate, Blood Pressure)
Rationale: To establish baseline and monitor for anticholinergic effects like tachycardia.
Timing: Prior to administration
Assessment of Symptoms
Rationale: To establish baseline severity of symptoms being treated (e.g., GI spasms, secretions).
Timing: Prior to administration
Urinary output/history of urinary retention
Rationale: To assess risk of urinary retention, a common anticholinergic side effect.
Timing: Prior to administration
Routine Monitoring
Heart Rate
Frequency: Periodically during treatment, especially with higher doses or in susceptible patients.
Target: Within patient's normal range, or as clinically indicated.
Action Threshold: Significant tachycardia (e.g., >100 bpm or significant increase from baseline) or palpitations.
Urinary Output/Bladder Distention
Frequency: Regularly, especially in elderly or those with prostatic hypertrophy.
Target: Adequate urinary output, no signs of retention.
Action Threshold: Decreased urinary output, bladder distention, or patient complaint of inability to void.
Bowel Function
Frequency: Daily
Target: Regular bowel movements.
Action Threshold: Severe constipation or signs of paralytic ileus.
Mental Status/CNS Effects
Frequency: Periodically, especially in elderly or those with pre-existing cognitive impairment.
Target: Alert and oriented, no new confusion or agitation.
Action Threshold: New onset of confusion, disorientation, hallucinations, or agitation.
Symptom Relief
Frequency: As needed, based on patient's condition.
Target: Reduction in target symptoms (e.g., abdominal pain, spasms, excessive secretions).
Action Threshold: Lack of efficacy or worsening of symptoms.
Symptom Monitoring
- Dry mouth
- Blurred vision
- Urinary hesitancy or retention
- Constipation
- Tachycardia
- Dizziness
- Confusion
- Agitation
- Headache
- Nausea/vomiting
Special Patient Groups
Pregnancy
Pregnancy Category C. Use only if the potential benefit justifies the potential risk to the fetus. Animal reproduction studies have shown an adverse effect on the fetus, but there are no adequate and well-controlled studies in humans.
Trimester-Specific Risks:
First Trimester:
Potential for fetal harm based on animal studies; human data limited.
Second Trimester:
Potential for fetal harm based on animal studies; human data limited.
Third Trimester:
Potential for fetal harm based on animal studies; human data limited. May inhibit uterine contractions.
Lactation
Excreted in breast milk. May decrease milk production. Use with caution. Monitor breastfed infant for anticholinergic effects (e.g., constipation, drowsiness).
Infant Risk:
L3 (Moderately safe; probably compatible, but caution advised).
Pediatric Use
Use with caution. Infants and young children may be more susceptible to the toxic effects of anticholinergics. Dosing must be carefully individualized and is often lower than adult doses. Risk of hyperthermia due to suppression of sweating.
Geriatric Use
Use with caution, starting with lower doses. Elderly patients are more susceptible to anticholinergic adverse effects, particularly CNS effects (confusion, delirium, hallucinations), urinary retention, and constipation. Increased risk of falls due to dizziness or blurred vision.
Clinical Information
Clinical Pearls
- Hyoscyamine injection is useful for rapid relief of acute GI spasms, irritable bowel syndrome exacerbations, or as a pre-operative agent to reduce secretions.
- Always assess for contraindications such as glaucoma (narrow-angle), myasthenia gravis, paralytic ileus, or obstructive uropathy (e.g., BPH with urinary retention).
- Monitor for signs of anticholinergic toxicity, especially in vulnerable populations (elderly, renally impaired).
- Can be used to differentiate between functional spasms and organic obstruction in acute abdominal pain, but caution is advised as it can mask symptoms of serious conditions.
- Patients should be advised about potential for dry mouth, blurred vision, and urinary retention.
Alternative Therapies
- Dicyclomine (oral, IM)
- Atropine (injection)
- Scopolamine (transdermal patch, injection)
- Glycopyrrolate (oral, injection)
- Propantheline (oral)
- Belladonna alkaloids (e.g., Donnatal - combination product)
Cost & Coverage
Average Cost:
Relatively inexpensive (generic) per 1ml vial
Generic Available:
Yes
Insurance Coverage:
Tier 1 or 2 (Generic)
General Drug Facts
If your symptoms or health problems persist or worsen, it is essential to contact your doctor promptly. To ensure safe use, never share your medication with others, and do not take medication prescribed for someone else. Store all medications in a secure location, out of reach of children and pets, to prevent accidental ingestion. Dispose of unused or expired medications properly. Unless instructed to do so by a healthcare professional or pharmacist, do not flush medications down the toilet or drain. If you are unsure about the correct disposal method, consult your pharmacist, as they can provide guidance on available drug take-back programs in your area. Some medications may come with an additional patient information leaflet, which can be obtained from your pharmacist. If you have any questions or concerns about your medication, it is crucial to discuss them with your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately contact your local poison control center or seek medical attention. Be prepared to provide information about the medication taken, the amount, and the time it occurred, as this will aid in prompt and effective treatment.