belladonna alkaloids/phenobarbital

Action and Spectrum

Actions and Spectrum: 

belladonna alkaloids and phenobarbital are commonly used medications with different mechanisms of action. 

belladonna alkaloids, also known as anticholinergics, are a group of drugs that block the activity of acetylcholine, a neurotransmitter in the nervous system that controls the contraction of muscles, including those in the digestive tract, bladder, and eyes. By inhibiting the activity of acetylcholine, belladonna alkaloids can cause the relaxation of smooth muscles, leading to decreased spasms and pain. belladonna alkaloids also have other effects, such as reducing saliva and bronchial secretions and dilating the pupils of the eyes. 

phenobarbital, on the other hand, is a barbiturate that works by enhancing the activity of the neurotransmitter gamma-aminobutyric acid (GABA) in the brain. GABA is an inhibitory neurotransmitter that helps regulate other neurotransmitters’ activity in the brain. By enhancing the activity of GABA, phenobarbital can reduce the excitability of neurons in the brain, leading to sedation, relaxation, and a reduction in seizures. 

When used together, belladonna alkaloids and phenobarbital can synergize in treating specific conditions, such as irritable bowel syndrome (IBS) and other gastrointestinal disorders. The combination can help reduce muscle spasms and pain in the digestive tract while providing sedation and relaxation. However, it is essential to note that both medications can have side effects and interactions with other drugs, so it is essential to use them under the guidance of a physician. 

Drug Interaction

Adverse Reaction

Frequency not defined 

belladonna alkaloids 

Blurred vision 

Dizziness 

Sedation 

Dry mouth 

Constipation 

Urinary retention 

phenobarbital 

Paradoxical excitement 

Confusion  

Hyperactivity 

Depression 

Excitement 

Respiratory depression 

Drowsiness 

Ataxia 

Fatigue 

Irritability 

Restlessness 

Dizziness 

Nystagmus 

Vertigo 

Paresthesia 

Dysarthria 

Stevens-Johnson syndrome 

Osteomalacia 

Rickets 

Hepatotoxicity 

Megaloblastic anemia 

Mental dullness 

Diarrhea 

Black Box Warning

Black Box Warning: 

The combination of belladonna alkaloids and phenobarbital has a black box warning from the U.S. Food and Drug Administration (FDA) due to the risk of abuse, misuse, and addiction.

The warning states that these medications can lead to physical and psychological dependence, particularly with long-term or high doses. Patients with a history of drug abuse or addiction should be monitored closely while taking these medications. 

Contraindication / Caution

Contraindication/Caution: 

Contraindication 

belladonna alkaloids and phenobarbital have several contraindications and precautions that patients should be aware of before using. These include: 

• Hypersensitivity or allergy to belladonna alkaloids, phenobarbital, or any ingredients in these medications. 
• Glaucoma, which can be worsened by the dilation of the pupils caused by belladonna alkaloids. 
• Severe respiratory conditions, such as asthma, chronic obstructive pulmonary disease (COPD), or emphysema, as the sedative effects of phenobarbital, can cause respiratory depression. 
• Liver /kidney disease, as these conditions can affect the metabolism and excretion of belladonna alkaloids and phenobarbital. 
• Pregnancy or breastfeeding, as these medications can adversely affect the developing fetus or nursing infant. 
• Cardiovascular diseases, such as heart failure or arrhythmias, as belladonna alkaloids can increase heart rate, and phenobarbital can cause hypotension. 
• Myasthenia gravis is a neuromuscular disorder that can exacerbate the anticholinergic effects of belladonna alkaloids. 

Caution 

there are several cautions that patients should be aware of before using belladonna alkaloids and phenobarbital. These include: 

• Age: These medications should be used cautiously in elderly patients, as they may be more susceptible to sedative and anticholinergic effects. 
• Children: belladonna alkaloids and phenobarbital should not be used in children without the guidance of a pediatrician. 
• Alcohol: Patients should have to avoid consuming alcohol while taking these medications, as it can increase the sedative effects and impair cognitive and motor function. 
• Driving or operating machinery: Patients should use caution when driving or operating machinery while taking these medications, as they can cause drowsiness, dizziness, and blurred vision. 
• Seizure disorders: Patients with a history of seizure disorders should use caution when taking phenobarbital, as it can lower the seizure threshold and increase the risk of seizures. 
• Mental health disorders: Patients with a history of mental health disorders, such as depression or anxiety, should be monitored closely while taking these medications, as they can worsen these conditions. 
• Other medical conditions: Patients with other medical conditions, such as gastrointestinal obstruction, urinary retention, or hyperthyroidism, should use these medications cautiously, as they can exacerbate them. 

Pregnancy / Lactation

Pregnancy consideration:  

US FDA pregnancy category: C 

Lactation:   

Excreted into human milk is Not known. 

Pregnancy category: 

• Category A: well-controlled and Satisfactory studies do not show risk to the fetus in the first/later trimester.        
• Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women        
• Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.       
• Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.        
• Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.        
• Category N: There is no data available for the drug under this category 

Pharmacology

Pharmacology: 

belladonna alkaloids are a group of natural plant alkaloids, including atropine, hyoscyamine, and scopolamine. These alkaloids work by blocking the action of the neurotransmitter acetylcholine, which regulates many bodily functions, including muscle movement, glandular secretion, and dilation of blood vessels. 

Stocking acetylcholine receptors has various effects, including reducing muscle spasms and secretions, dilating the pupils, and decreasing gastrointestinal motility and secretions. These effects can help treat conditions such as irritable bowel syndrome, gastric ulcers, and biliary colic. 

phenobarbital is a barbiturate medication that works by enhancing the activity of the neurotransmitter gamma-aminobutyric acid (GABA), which is involved in regulating neuronal activity. This results in a sedative and anticonvulsant effect that can be useful in treating conditions such as epilepsy, anxiety, and insomnia. 

The combination of belladonna alkaloids and phenobarbital can provide a synergistic effect that can enhance the therapeutic benefits of both medications. The belladonna alkaloids can help relieve spasms and cramping, while phenobarbital can provide sedative and anticonvulsant effects. 

Pharmacodynamics: 

Mechanism of action: The drug combination works through a specific mechanism of action. It provides natural belladonna alkaloids in a fixed ratio, which possess anticholinergic properties and competitively inhibit acetylcholine actions at muscarinic receptors. This anticholinergic/antispasmodic action is further enhanced by phenobarbital, which depresses the sensory and motor cortex and cerebellum, resulting in mild sedation. 

Pharmacokinetics: 

Absorption 

belladonna alkaloids are absorbed through the gastrointestinal tract. The onset of action can be relatively rapid, with effects usually felt within 30-60 minutes after oral administration. 

phenobarbital is well-absorbed orally, with peak plasma concentrations occurring 4-6 hours after ingestion. 

Distribution 

Once absorbed, belladonna alkaloids are distributed throughout the body via the bloodstream. They have a high affinity for tissues such as the brain, heart, and lungs. 

Once absorbed, phenobarbital is distributed throughout the body via the bloodstream. It has a high affinity for tissues such as the brain, liver, and kidneys. 

Metabolism 

belladonna alkaloids undergo extensive metabolism in the liver. The primary metabolic pathway is hydrolysis, where the ester bonds are broken down into their respective acid and alcohol components. 

phenobarbital undergoes extensive metabolism in the liver. The primary metabolic pathway is oxidation, which converts the drug into inactive metabolites. 

Elimination and Excretion 

The metabolites of belladonna alkaloids are excreted primarily in the urine, with a small amount excreted in the feces. The half-life of these medications can vary depending on the specific alkaloid. 

The metabolites of phenobarbital are excreted primarily in the urine, with a small amount excreted in the feces. The half-life of phenobarbital can vary depending on the age and health of the patient, with a longer half-life in infants and a shorter half-life in adults. 

Adminstartion

Administration: 

Oral administration 

belladonna alkaloids and phenobarbital are usually administered orally in tablet or capsule form. The dosage, frequency of administration will depend on the patient’s age, weight, medical condition, and response to treatment. 

It is essential to take these medications exactly as the healthcare provider prescribes. Patients should not enhance their dose or take these medications more frequently than recommended, as doing so can increase the risk of adverse effects. 

Patients should take these medications with a full glass of water and may take them with or without food, depending on their preference. However, taking them with food may help reduce gastrointestinal side effects. 

Patients should also avoid crushing or chewing tablets or capsules, as this can affect the absorption and effectiveness of the medication. If patients have difficulty swallowing the medication, they should talk to their healthcare provider about alternative administration methods. 

Patients should continue taking these medications for the entire prescribed course, even if their symptoms improve. Stopping the medication early can lead to a relapse or worsening of symptoms. 

If a dose is missed, it is recommended to take it as soon as possible. However, if the next scheduled dose is missed, it should be skipped and the following dose should be taken at the appropriate time. It is important to avoid taking a double dose of the medication to compensate for the missed dose.

Patients must follow up with their healthcare provider regularly while taking these medications to monitor their response to treatment and adjust the dosage if needed. 

Patient Information Leaflet

Patient information leaflet 

Generic Name:  belladonna alkaloids/phenobarbital 

Pronounced: [ bell-a-DON-a/fee-noe-BAR-bih-tal ] 

Why do we use belladonna alkaloids/phenobarbital? 

belladonna alkaloids and phenobarbital are often used together in combination as a prescription medication for the treatment of various conditions, including: 

• Irritable bowel syndrome (IBS): belladonna alkaloids can help relieve gastrointestinal spasms and cramping, while phenobarbital can have a sedative effect that can reduce anxiety-related symptoms. 
• Gastric and duodenal ulcers: belladonna alkaloids can help reduce stomach acid secretion and relieve muscle spasms, while phenobarbital can have a sedative effect that can reduce anxiety-related symptoms. 
• Gastroesophageal reflux disease (GERD): belladonna alkaloids can help reduce stomach acid secretion and relieve muscle spasms, while phenobarbital can have a sedative effect that can reduce anxiety-related symptoms. 
• Biliary colic: belladonna alkaloids can help relieve muscle spasms in the bile ducts, while phenobarbital can have a sedative effect that can reduce anxiety-related symptoms. 
• Epilepsy: phenobarbital is an antiepileptic medication that can help prevent or reduce seizures. 
• Anxiety and tension: phenobarbital can have a sedative effect that can help reduce anxiety-related symptoms. 
• Insomnia: phenobarbital can have a sedative effect that can help promote sleep. 
• Pain relief: belladonna alkaloids can help relieve muscle spasms and cramping, which can be helpful for certain types of pain, such as menstrual cramps or back pain.