GOAB 5

Indications

• Dry eye conditions
• Tear deficiency
• Keratoconjunctivitis sicca

Dosage

Children: Apply as required, typically in the form of eye drops.

Adults: Apply as required, typically in the form of eye drops.

Mechanism of action

Hypromellose acts by forming a viscous gel upon contact with the ocular surface, which helps to retain moisture and protect against irritants. This gel-like property enhances the stability of the tear film and reduces evaporation, thereby alleviating symptoms associated with dry eye conditions.

Pharmacodynamics

The pharmacodynamic effects of hypromellose are primarily related to its ability to mimic natural tears, providing lubrication to the ocular surface. This lubrication reduces friction during blinking and maintains corneal hydration, which is critical for ocular comfort and health. Its high viscosity also contributes to prolonged retention time on the eye surface.

Pharmacokinetics

Hypromellose is administered topically as eye drops and is not significantly absorbed systemically. The retention time of hypromellose on the ocular surface is enhanced due to its viscosity, allowing for extended relief of dry eye symptoms. The elimination of hypromellose occurs primarily through drainage from the eye and dilution by the natural tear fluid.

Adverse effects

• Temporary visual disturbance
• Eye irritation

Precautions

• Should not be used during contact lens wear
• Use with caution in patients with known hypersensitivity to any component of the formulation

Pregnancy

Hypromellose is generally considered safe for use during pregnancy. However, it should be used only if clearly needed and after consulting a healthcare provider.

Breast-feeding

Hypromellose is unlikely to affect breastfed infants when used as directed, but consultation with a healthcare provider is advisable.

Storage

Store in a cool, dry place away from direct sunlight. Once opened, use within a specified period as indicated on the packaging.

Formulations

• {'name': 'Teardew', 'concentration': '0.3%', 'form': 'eye drops', 'volume': '10 ml'}
• {'name': 'Xailin Hydrate', 'concentration': '0.3%', 'form': 'eye drops', 'volume': '10 ml'}
• {'name': 'AacuLose', 'concentration': '0.3%', 'form': 'eye drops', 'volume': '10 ml'}
• {'name': 'Artelac', 'concentration': '0.32%', 'form': 'eye drops', 'volume': '10 ml'}
• {'name': 'Lacrilube', 'concentration': '2 mg/g', 'form': 'eye ointment', 'volume': '3.5 g'}
• {'name': 'Celluvisc', 'concentration': '1%', 'form': 'eye drops', 'volume': '0.4 ml unit dose'}

Indications

• Urinary frequency
• Urgency
• Incontinence associated with overactive bladder
• Incontinence associated with neurogenic bladder instability

Dosage

Children: Refer to the BNF for Children for appropriate dosing information, as specific pediatric dosing is not provided.

Adults: 15 mg once daily, increased if necessary to a maximum of 30 mg once daily for immediate-release formulations. For modified-release capsules, the usual dose is 30 mg once daily.

Mechanism of action

Solifenacin succinate selectively inhibits the M3 subtype of muscarinic acetylcholine receptors, which are primarily responsible for bladder contraction. By blocking these receptors, solifenacin reduces detrusor muscle overactivity, leading to decreased urinary frequency and urgency.

Pharmacodynamics

The pharmacodynamic effects of solifenacin include a reduction in bladder contractions, increased bladder capacity, and diminished urgency to void. Its antimuscarinic properties help alleviate the symptoms associated with overactive bladder, providing symptomatic relief in patients with urinary incontinence.

Pharmacokinetics

Solifenacin is well absorbed after oral administration, with peak plasma concentrations occurring approximately 3 to 8 hours post-dose. It has a bioavailability of around 90% and is extensively metabolized in the liver via CYP3A4. The elimination half-life is approximately 45 hours, allowing for once-daily dosing. Renal impairment can affect its clearance, necessitating dose adjustments in patients with reduced creatinine clearance.

Contra-indications

• Severe hepatic impairment
• Moderate to severe renal impairment
• Hypersensitivity to solifenacin or any of its excipients

Adverse effects

• Abdominal pain
• Fatigue
• Altered taste
• Tremor
• Restlessness
• Hallucination
• Anaphylactic reaction
• Delirium
• Dysphonia
• Muscle weakness
• QT interval prolongation

Interactions

• Anticholinergic agents may enhance effects
• CYP3A4 inhibitors (e.g., ketoconazole) may increase solifenacin levels
• CYP3A4 inducers (e.g., rifampicin) may decrease solifenacin levels
• Concurrent use of medications that prolong QT interval should be approached with caution

Precautions

• Caution in patients with gastrointestinal disorders
• Caution in elderly patients due to increased sensitivity
• Caution in patients with a history of glaucoma
• Caution in patients with urinary retention

Pregnancy

Manufacturer advises caution due to lack of information available on safety in pregnancy.

Breast-feeding

Manufacturer advises avoiding use as solifenacin is present in milk in animal studies.

Storage

Store at room temperature, away from moisture and heat. Keep out of reach of children.

Formulations

• Oral solution: Solifenacin succinate 1 mg per 1 ml
• Modified-release capsule: Solifenacin succinate 5 mg
• Modified-release capsule: Solifenacin succinate 30 mg

Indications

• Energy source
• Dietary fiber supplement
• Source of vitamins and minerals
• Antioxidant support

Dosage

Children: Corn can be introduced to children as part of a balanced diet. There is no specific paediatric dosage; it should be given according to age-appropriate dietary guidelines.

Adults: Corn can be consumed in various forms as part of a balanced diet. There is no specific adult dosage; intake should be based on dietary preferences and nutritional needs.

Mechanism of action

The primary component of corn is starch, which is a polysaccharide composed of glucose units. Upon ingestion, starch is broken down into glucose by enzymes such as amylase in the digestive system. The glucose is then absorbed into the bloodstream, providing energy to cells throughout the body. Corn also contains antioxidants such as lutein and zeaxanthin, which may help protect against oxidative stress and support eye health.

Pharmacodynamics

Corn is mainly metabolized for energy due to its high carbohydrate content. The dietary fiber in corn aids in digestion and promotes satiety. Additionally, the presence of vitamins and minerals contributes to overall health, supporting various bodily functions including immune response and bone health. The antioxidants in corn may help reduce inflammation and lower the risk of chronic diseases.

Pharmacokinetics

The digestion and absorption of corn depend on its form (whole kernel, cornmeal, corn syrup, etc.). Generally, carbohydrates are digested and absorbed relatively quickly, with glucose appearing in the bloodstream shortly after consumption. The fiber content can slow digestion and help maintain stable blood sugar levels. The bioavailability of nutrients from corn can vary based on processing methods, such as cooking or milling.

Pregnancy

Corn is generally considered safe during pregnancy. It provides essential nutrients such as fiber, vitamins, and minerals, but should be consumed in moderation as part of a balanced diet.

Breast-feeding

Corn is safe for consumption while breastfeeding. It can provide important nutrients, but it's advisable to monitor for any allergic reactions in infants.

Storage

Store corn in a cool, dry place. Fresh corn should be kept in the refrigerator and consumed within a few days for optimal freshness.

Formulations

• Fresh corn
• Canned corn
• Frozen corn
• Cornmeal
• Corn syrup
• Corn oil

Indications

• Lactose intolerance
• As a filler or excipient in pharmaceutical formulations

Dosage

Children: Refer to the BNF for Children for specific dosing information based on age and clinical context.

Adults: Refer to the BNF for specific dosing information based on clinical context.

Mechanism of action

Lactose is metabolized in the intestine by the enzyme lactase into its constituent monosaccharides, glucose and galactose. In individuals with lactase deficiency, unabsorbed lactose passes into the colon, where it is fermented by bacteria, leading to gas production and osmotic effects that contribute to diarrhea.

Pharmacodynamics

The pharmacodynamics of lactose are primarily related to its effects on gastrointestinal function. In healthy individuals, lactose is effectively broken down into glucose and galactose, which are absorbed and utilized for energy. In individuals with lactose intolerance, the unabsorbed lactose can cause osmotic diarrhea and colonic fermentation, leading to discomfort and symptoms associated with lactose intolerance.

Pharmacokinetics

Lactose is not absorbed in the gastrointestinal tract until it is hydrolyzed into glucose and galactose by lactase. The absorption of glucose and galactose occurs in the small intestine. The half-life is not applicable as lactose is not typically administered as a medication but is rather ingested as a natural component of food. Its metabolism primarily occurs in the intestine.

Adverse effects

• Bloating
• Diarrhea
• Abdominal pain
• Flatulence

Precautions

• Use with caution in patients with lactose intolerance.
• Consider potential for gastrointestinal upset in sensitive individuals.

Pregnancy

Lactose is generally considered safe for use during pregnancy. However, consult a healthcare professional for individual advice.

Breast-feeding

Lactose is safe to use while breastfeeding, as it is a natural sugar present in breast milk.

Storage

Store in a cool, dry place, away from direct sunlight.

Formulations

• Powder
• Granules
• Tablets
• Syrup

Indications

• Tablet coating
• Granule coating
• Improvement of drug stability
• Taste masking
• Aesthetic enhancement of pharmaceuticals

Dosage

Children: Dosage will depend on the specific formulation and active ingredients of the medication being coated. Refer to the specific product information for guidance.

Adults: Dosage will depend on the specific formulation and active ingredients of the medication being coated. Refer to the specific product information for guidance.

Mechanism of action

Opadry functions primarily as a coating polymer that adheres to the surface of tablets or granules, creating a protective layer. This layer can control the release of the active ingredient and protect it from environmental factors such as moisture and light. The specific composition of Opadry can vary, but it typically includes film-forming agents, plasticizers, and colorants that work together to achieve the desired coating characteristics.

Pharmacodynamics

The pharmacodynamics of Opadry is largely focused on its physical and chemical properties rather than specific biological interactions. The coating alters the dissolution characteristics of the drug, potentially leading to modified release profiles. This can enhance drug bioavailability or control the release rate of the active ingredient, thereby impacting the therapeutic effect.

Pharmacokinetics

As a coating agent, Opadry itself is not absorbed into the systemic circulation and does not have pharmacokinetic properties related to absorption, distribution, metabolism, or excretion of an active pharmaceutical ingredient. Its impact on pharmacokinetics is indirect, as it affects how the active drug is released and absorbed in the gastrointestinal tract.

Pregnancy

Opadry is a film-coating agent, and specific studies on its effects during pregnancy are not well-documented. Generally, it is advisable to use medications cautiously during pregnancy. Consult a healthcare provider for guidance.

Breast-feeding

Limited data are available regarding the safety of Opadry during breastfeeding. It is recommended to consult a healthcare provider before use.

Storage

Store in a cool, dry place away from direct sunlight and moisture. Keep out of reach of children.

Formulations

• Opadry OY - a coating system for oral solid dosage forms
• Opadry II - a polymer-based coating system for tablet and capsule applications

Indications

• Nasal congestion due to colds
• Allergic rhinitis
• Sinusitis
• Hypotension during anesthesia

Dosage

Children: Refer to BNF for Children for appropriate pediatric dosing.

Adults: Refer to specific guidelines for adult dosing as it varies based on the formulation and indication.

Mechanism of action

Phenylephrine exerts its effects by selectively stimulating alpha-1 adrenergic receptors located on the smooth muscle of blood vessels. This stimulation causes vasoconstriction, resulting in increased vascular resistance and elevated blood pressure. In the nasal mucosa, the vasoconstriction reduces the volume of blood in the area, leading to decreased edema and congestion.

Pharmacodynamics

The pharmacodynamic effects of phenylephrine include increased systemic vascular resistance and potential increase in heart rate due to reflex tachycardia. Its action is dose-dependent, with low doses primarily causing vasoconstriction and higher doses potentially affecting heart rate and cardiac output. The onset of action for nasal congestion relief is typically within minutes, while its duration of action lasts for several hours.

Pharmacokinetics

Phenylephrine is administered orally, intravenously, or nasally, with varying bioavailability depending on the route. When taken orally, its bioavailability is low due to extensive first-pass metabolism in the liver. Peak plasma concentrations occur approximately 1 to 2 hours after oral administration. The half-life of phenylephrine is about 2 to 3 hours. It is metabolized by monoamine oxidase and sulfation, with renal excretion of the metabolites. Caution is advised in patients with hepatic impairment due to altered metabolism.

Dosage

Children: Refer to specific drug formulations and product labels as purified substances can vary widely in their use and dosing.

Adults: Refer to specific drug formulations and product labels as purified substances can vary widely in their use and dosing.

Mechanism of action

The mechanism of action for purified compounds varies widely depending on the specific substance. Generally, purified drugs exert their effects by interacting with specific biological targets, such as receptors, enzymes, or ion channels, leading to a desired therapeutic effect. This interaction can involve binding to receptors to activate or inhibit signaling pathways, modulating enzymatic activity, or altering physiological processes.

Pharmacodynamics

Pharmacodynamics describes the effects of a drug on the body and the relationship between drug concentration and effect. For purified drugs, this can involve dose-response relationships and the time course of their action. The purified form often enhances potency and reduces variability in response among patients, which can lead to more predictable therapeutic outcomes. The overall effect is determined by the drug's affinity for its target, the efficacy of the drug-receptor interaction, and the downstream signaling pathways activated as a result of this interaction.

Pharmacokinetics

Pharmacokinetics involves the absorption, distribution, metabolism, and excretion (ADME) of a drug. For purified substances, absorption can be more efficient due to the absence of impurities that may affect solubility or stability. Distribution may also be enhanced, leading to higher bioavailability. Metabolism can be influenced by the structure of the purified compound, as it may be metabolized more readily by liver enzymes. Excretion typically occurs through the kidneys or liver, depending on the molecular characteristics of the purified drug.

Pregnancy

Consult with a healthcare professional, as the safety of purified forms of medications during pregnancy may vary depending on the specific substance.

Breast-feeding

Consult with a healthcare professional, as the safety of purified forms of medications during breastfeeding may vary depending on the specific substance.

Storage

Store in a cool, dry place, away from light and moisture, and keep out of reach of children.

Indications

• Overactive bladder
• Urinary incontinence
• Urinary urgency
• Urinary frequency

Dosage

Children: Safety and efficacy have not been established in children; refer to BNF for Children for specific dosing recommendations.

Adults: The usual adult dose is 5 mg once daily, which may be increased to 10 mg once daily based on individual patient response and tolerability.

Mechanism of action

Solifenacin competitively inhibits muscarinic receptors, with a high affinity for M3, M1, and M2 receptors. By antagonizing the M3 receptor, it prevents detrusor muscle contraction, while antagonism of the M2 receptor may inhibit contraction of bladder smooth muscle, thereby alleviating symptoms of overactive bladder.

Pharmacodynamics

The drug effectively reduces symptoms associated with overactive bladder by blocking the muscarinic receptors. Its long duration of action allows for once-daily dosing, providing consistent symptom control. However, patients should be monitored for potential adverse reactions such as angioedema and anaphylaxis, which can occur in some individuals.

Pharmacokinetics

Solifenacin is absorbed well following oral administration, with peak plasma concentrations occurring approximately 3 to 8 hours after dosing. It undergoes hepatic metabolism primarily via cytochrome P450 enzymes, leading to various metabolites, some of which may retain pharmacological activity. The elimination half-life is around 45 to 68 hours, supporting its once-daily dosing regimen. Renal and hepatic function may influence the drug's clearance.

Adverse effects

• dry mouth
• constipation
• blurred vision
• urinary retention
• angioedema
• anaphylaxis

Interactions

• clozapine+solifenacin: Unknown (additive effect)
• cobicistat+solifenacin: Unknown (increases exposure)
• idelalisib+solifenacin: Unknown (increases exposure)
• clarithromycin+solifenacin: Unknown (increases exposure)
• mitotane+solifenacin: Unknown (decreases exposure)
• rifampicin+solifenacin: Unknown (decreases exposure)
• antipsychotics, second generation+solifenacin: Unknown (additive effect)

Pregnancy

The safety of solifenacin during pregnancy has not been established. Use only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

Solifenacin is excreted in breast milk. Caution is advised when administered to nursing women.

Storage

Store in a cool, dry place, away from direct sunlight and moisture. Keep out of reach of children.

Formulations

• tablets

Indications

• Nutritional supplementation
• Energy source in enteral nutrition
• Excipient in pharmaceutical formulations

Dosage

Children: Refer to specific guidelines or product inserts for dosing information, as it can vary based on the context of use.

Adults: Refer to specific guidelines or product inserts for dosing information, as it can vary based on the context of use.

Mechanism of action

Starch is broken down into glucose units by enzymes such as amylase during digestion. The glucose is then absorbed in the intestines and utilized for energy production in the body's cells. This pathway involves hydrolysis of the glycosidic bonds, converting starch into simpler sugars.

Pharmacodynamics

Starch primarily serves as an energy source. Its digestion and absorption lead to an increase in blood glucose levels, which provides energy for metabolic processes. In this context, it plays a crucial role in maintaining energy homeostasis in the body.

Pharmacokinetics

Starch is not absorbed in its polymeric form; it must first be enzymatically hydrolyzed into simpler sugars such as maltose and glucose. The digestion and absorption of starch occur predominantly in the small intestine, with glucose being readily absorbed into the bloodstream. The rate of absorption can vary depending on the type of starch and its physical form.

Adverse effects

• Allergic reactions
• Gastrointestinal discomfort
• Diarrhea
• Constipation

Precautions

• Use with caution in individuals with known allergies to starch or starch derivatives
• Monitor for gastrointestinal symptoms in patients with a history of digestive disorders

Pregnancy

Starch is generally considered safe for use during pregnancy. However, it should be consumed in moderation as part of a balanced diet.

Breast-feeding

Starch is deemed safe for nursing mothers when used in moderation as part of a balanced diet.

Storage

Store in a cool, dry place away from moisture and direct sunlight.

Formulations

• Powder
• Granules
• Tablets
• Suspensions

Dosage

Children: Refer to the BNF for Children for appropriate paediatric dosing information.

Adults: Refer to the specific BNF guidelines for dosing information as it may vary based on the condition being treated.

Mechanism of action

The mechanism of action for White involves its interaction with specific biological pathways, leading to the desired pharmacological effects. The precise pathways may include modulation of receptor activity or alteration of enzyme function, although specific details are not provided.

Pharmacodynamics

Pharmacodynamics of White includes its effects on the body, including therapeutic effects and potential side effects. As a compound, it may exert its influence on multiple physiological systems, which can lead to changes in symptoms or disease progression.

Pharmacokinetics

Pharmacokinetics of White involves its absorption, distribution, metabolism, and excretion. Understanding these parameters can help predict how the drug behaves in the body, including onset of action and duration of effect. Detailed pharmacokinetic data is not specified.

Mechanism of action

Solifenacin is a competitive muscarinic receptor antagonist. It has the highest affinity for M3, M1, and M2 muscarinic receptors. 80% of the muscarinic receptors in the bladder are M2, while 20% are M3. Solifenacin's antagonism of the M3 receptor prevents contraction of the detrusor muscle, while antagonism of the M2 receptor may prevent contraction of smooth muscle in the bladder.

Pharmacodynamics

Solifenacin antagonizes the M2 and M3 muscarinic receptors in the bladder to treat an overactive bladder. It has a long duration of action as it is usually taken once daily. Patients taking solifenacin should be aware of the risks of angioedema and anaphylaxis.