Usage
Belladonna dry extract is prescribed for various conditions involving smooth muscle spasms, such as irritable bowel syndrome (IBS), diverticulitis, peptic ulcers, and other gastrointestinal disorders. It’s also used to reduce excessive secretions (like saliva, sweat, and gastric acid) and to treat bradycardia (slow heart rate). The drug’s pharmacological classifications include anticholinergic, antimuscarinic, antispasmodic, and parasympatholytic.
Belladonna dry extract’s mechanism of action primarily involves competitive antagonism of acetylcholine at muscarinic receptors, particularly M1, M2, and M3 subtypes. This inhibition prevents acetylcholine from binding and exerting its effects, resulting in reduced smooth muscle contractions and glandular secretions.
Alternate Names
Belladonna dry extract is also known as Atropa belladonna, deadly nightshade, or dwale. Brand names containing belladonna extract include Donnatal (in combination with phenobarbital).
How It Works
Pharmacodynamics: Belladonna alkaloids, primarily atropine, hyoscyamine, and scopolamine, exert their effects by blocking the action of acetylcholine at muscarinic receptors located in smooth muscles, glands, and the central nervous system. This blockade leads to a decrease in smooth muscle tone, reduced secretions (saliva, sweat, gastric acid), increased heart rate, and dilation of pupils.
Pharmacokinetics: Belladonna extract is readily absorbed from the gastrointestinal tract. Atropine and hyoscyamine are metabolized in the liver, while scopolamine undergoes some metabolism in the liver but is primarily excreted unchanged in urine. Elimination pathways involve both hepatic metabolism and renal excretion. The specific CYP enzymes involved in belladonna alkaloid metabolism are not fully elucidated.
Mode of Action: The primary mode of action is competitive antagonism of acetylcholine at muscarinic receptors, primarily subtypes M1 (neural), M2 (cardiac), and M3 (glandular/smooth muscle). This inhibits acetylcholine-mediated effects like smooth muscle contraction, glandular secretions, and slowing of heart rate.
Receptor Binding/Enzyme Inhibition/Neurotransmitter Modulation: Belladonna extract primarily acts by binding to and blocking muscarinic cholinergic receptors. It does not significantly inhibit enzymes or directly modulate neurotransmitter release other than indirectly affecting acetylcholine’s actions by blocking its receptors.
Dosage
Dosage information for belladonna dry extract is limited and varies significantly based on the formulation and specific condition being treated. Always follow the prescribed dosage instructions. The following is general information and does not substitute professional medical advice.
Standard Dosage
Adults:
The usual initial dose of belladonna extract is 15–30 mg (equivalent to 0.187–0.374 mg of belladonna alkaloids) three or four times daily. Belladonna tincture: 0.6–1 mL (0.18–0.3 mg of belladonna alkaloids) three or four times daily. Dosage should be titrated based on individual patient response.
Children:
Safety and efficacy not established. Belladonna is generally considered unsafe for use in children. Consult a pediatrician for potential alternatives.
Special Cases:
- Elderly Patients: Start at the lower end of the dosing range due to increased sensitivity to anticholinergic effects and titrate cautiously. Monitor for mental confusion, constipation, dry mouth, and urinary retention.
- Patients with Renal Impairment: Use with caution; dosage adjustments may be needed.
- Patients with Hepatic Dysfunction: Use with caution; dosage adjustments may be needed.
- Patients with Comorbid Conditions: Use with extreme caution in patients with glaucoma, gastrointestinal obstructions, urinary retention, cardiovascular disease, and myasthenia gravis.
Clinical Use Cases
Specific dosage guidelines for clinical use cases are not well-established. Belladonna dry extract’s use in these situations is limited and should be individualized based on patient condition and under close monitoring. It is generally not recommended.
- Intubation: Use not recommended.
- Surgical Procedures: Not typically used.
- Mechanical Ventilation: Not typically used.
- Intensive Care Unit (ICU) Use: Use is limited.
- Emergency Situations: Not generally used.
Dosage Adjustments
Dosage modifications are necessary for patients with renal or hepatic impairment. Consult a physician for appropriate adjustments based on individual patient conditions.
Side Effects
Common Side Effects
Dry mouth, blurred vision, constipation, urinary hesitancy, dilated pupils, increased heart rate, dry skin, and reduced sweating.
Rare but Serious Side Effects
Confusion, hallucinations, delirium, seizures, rapid heartbeat, difficulty breathing, allergic reactions.
Long-Term Effects
Chronic use can lead to tolerance and potential complications related to anticholinergic effects, such as urinary retention and constipation.
Adverse Drug Reactions (ADR)
Severe allergic reactions, cardiac arrhythmias, angle-closure glaucoma exacerbation, toxic megacolon.
Contraindications
Glaucoma, urinary retention, severe ulcerative colitis, toxic megacolon, myasthenia gravis, unstable cardiovascular status, gastrointestinal obstructions, prostatic hypertrophy.
Drug Interactions
Anticholinergic drugs (e.g., antihistamines, tricyclic antidepressants), opioid analgesics, cisapride, potassium tablets/capsules.
Pregnancy and Breastfeeding
Belladonna dry extract is contraindicated during pregnancy and breastfeeding due to potential fetal harm and decreased milk production. It is classified as Pregnancy Category C, indicating potential risk to the fetus.
Drug Profile Summary
- Mechanism of Action: Muscarinic receptor antagonist.
- Side Effects: Dry mouth, blurred vision, constipation, urinary retention, confusion, hallucinations.
- Contraindications: Glaucoma, urinary retention, bowel obstruction, myasthenia gravis.
- Drug Interactions: Anticholinergics, opioids.
- Pregnancy & Breastfeeding: Contraindicated.
- Dosage: Variable, depending on formulation and condition. Adult dose: 15-30 mg three to four times daily.
- Monitoring Parameters: Heart rate, blood pressure, mental status, bowel and bladder function.
Popular Combinations
Belladonna extract is sometimes combined with phenobarbital for the treatment of gastrointestinal disorders.
Precautions
Use with extreme caution in elderly patients, patients with renal or hepatic impairment, and patients with pre-existing cardiovascular or gastrointestinal conditions. Avoid alcohol and other CNS depressants. Driving or operating machinery may be impaired.
FAQs (Frequently Asked Questions)
A: The recommended adult dose is 15-30 mg three or four times a day. Dosage needs to be individualized based on the patient’s condition and response to therapy. Pediatric use is generally not recommended.
A: Primarily used as an antispasmodic to treat conditions involving smooth muscle spasms such as IBS and other gastrointestinal disorders.
A: Common side effects include dry mouth, blurred vision, constipation, urinary hesitancy, and dilated pupils.
A: No, Belladonna dry extract is contraindicated during pregnancy due to potential harm to the fetus.
A: Serious side effects include confusion, hallucinations, seizures, rapid heartbeat, and difficulty breathing. Seek immediate medical attention if these occur.
A: Belladonna interacts with other anticholinergic medications, opioid analgesics, and cisapride. Concomitant use should be avoided or carefully monitored.
A: No, Belladonna dry extract is contraindicated in patients with glaucoma because it can exacerbate the condition.
A: Long-term use can lead to tolerance and potential complications related to anticholinergic effects, such as urinary retention and constipation.
A: Belladonna alkaloids are metabolized primarily in the liver and excreted through both hepatic and renal pathways.
This information is current as of February 16, 2025, and may be subject to change. This information is for general knowledge purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.
