LANPRO

Indications

• Gastro-oesophageal reflux disease
• Duodenal ulcer
• Benign gastric ulcer
• NSAID-associated gastric or duodenal ulcer
• Zollinger-Ellison syndrome

Dosage

Adults: 30 mg once daily for 4 weeks for duodenal ulcers, 30 mg once daily for 8 weeks for gastric ulcers, and 15 mg once daily for maintenance treatment. For gastro-oesophageal reflux disease, the usual dose is 15 mg

Mechanism of action

Lansoprazole is a prodrug that becomes activated in an acidic environment. Once protonated, it forms stable disulfide bonds with cysteine residues on the H+,K+-ATPase enzyme in parietal cells. This covalent binding leads to prolonged inhibition of gastric acid secretion, affecting both basal and stimulated acid production regardless of the stimulus.

Pharmacodynamics

Lansoprazole decreases gastric acid secretion by specifically targeting the H+,K+-ATPase enzyme, which catalyzes the final step in gastric acid secretion. It effectively heals duodenal ulcers and alleviates symptoms associated with acid secretion, such as heartburn, while also reducing pepsin secretion. Its action is effective in both daytime and nocturnal acid secretion, making it useful in treating various acid-related disorders.

Pharmacokinetics

Lansoprazole is absorbed after oral administration, with peak plasma concentrations usually occurring within 1-2 hours. It is extensively metabolized in the liver primarily via cytochrome P450 enzymes, leading to various metabolites that are excreted in urine. The half-life of lansoprazole is approximately 1.5 hours, but its acid-suppressive effects last longer due to its mechanism of action. The presence of food can affect the absorption rate, so it is typically recommended to take lansoprazole before meals.

Contra-indications

• Hypersensitivity to lansoprazole or any of its excipients
• Concurrent use with rilpivirine-containing products

Adverse effects

• Headache
• Diarrhoea
• Nausea
• Abdominal pain
• Constipation
• Flatulence
• Dizziness
• Fatigue
• Skin rash
• Elevated liver enzymes
• Acute interstitial nephritis
• Clostridium difficile-associated diarrhoea
• Bone fractures
• Hypomagnesemia

Interactions

• Increased risk of gastrointestinal infections due to reduced gastric acidity
• Apalutamide may decrease exposure when used with lansoprazole
• May alter the absorption of drugs that require an acidic environment for optimal absorption

Precautions

• Use with caution in patients with hepatic impairment
• Monitor for signs of Clostridium difficile infection in patients with prolonged therapy
• Consider risk of hypomagnesemia and associated complications

Pregnancy

Manufacturer advises to avoid use during pregnancy due to lack of adequate human data.

Breast-feeding

Specialist sources indicate use with caution, as lansoprazole is likely to be present in human milk, but in small amounts probably too low to be harmful.

Storage

Store below 25°C in a dry place, protect from light.

Formulations

• Gastro-resistant capsules
• Oral suspension
• Gastro-resistant tablets
• Gastro-resistant granules

Indications

• Low blood volume
• Hypovolemic shock
• Burns
• Cardiopulmonary bypass

Dosage

Children: Initially 10-20 mL per kilogram. Adjust according to the patient's condition and response, using 3.5-4% solution. Use under specialist supervision to mitigate the risk of fluid overload.

Adults: Dose according to requirements, typically administered intravenously. Consult product literature for specific dosing guidance.

Mechanism of action

Gelatin acts as a plasma expander by increasing the oncotic pressure in the vascular compartment, which helps to retain fluid within the bloodstream and restore circulating blood volume. This mechanism aids in maintaining blood pressure and improving tissue perfusion.

Pharmacodynamics

Gelatin solutions increase blood volume and improve hemodynamic stability in patients experiencing hypovolemic conditions. By drawing water into the vascular space, they help to counteract the effects of low blood volume, such as hypotension and compromised organ perfusion.

Pharmacokinetics

Gelatin is administered intravenously, and its effects can be observed relatively quickly. The half-life and the metabolic clearance depend on the formulation and concentration of the solution. Gelatin is gradually metabolized by macrophages and eliminated by the renal system. Close monitoring of fluid balance is essential, particularly in patients with cardiac or renal impairment.

Contra-indications

• Severe liver disease
• History of circulatory disease
• Severe cardiac disease

Adverse effects

• Fever
• Flushing
• Nausea
• Urticaria
• Rare or very rare shock

Interactions

• Calcium salts

Precautions

• Monitor cardiovascular and respiratory function
• Correct dehydration when administering
• Administer slowly to avoid rapid rise in blood pressure and cardiac failure
• Increased capillary permeability

Pregnancy

Consult product literature for specific guidance regarding use in pregnancy.

Breast-feeding

Consult product literature for specific guidance regarding use in breastfeeding.

Storage

Store at controlled room temperature, protect from light. Refer to product-specific storage instructions.

Formulations

• 5% solution for infusion
• 20% solution for infusion
• Concentrated solution (15-25% protein)
• Isotonic solution (3.5-5% protein)

Indications

• Chronic hepatitis C virus infection
• Genotype 1 HCV infection

Dosage

Children: Refer to BNF for Children for specific dosing information tailored to paediatric patients.

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

Mechanism of action

Paritaprevir inhibits the NS3/4A serine protease of the Hepatitis C Virus (HCV). This enzyme is responsible for cleaving the viral polypeptide into essential structural and nonstructural proteins necessary for the assembly of mature virus. By inhibiting NS3/4A, paritaprevir prevents viral replication and function.

Pharmacodynamics

At concentrations significantly above therapeutic levels, paritaprevir and its combination with ombitasvir do not prolong the QTc interval to a clinically relevant extent. This suggests a favorable safety profile concerning cardiac effects at therapeutic doses.

Pharmacokinetics

Paritaprevir is absorbed effectively after oral administration, with its pharmacokinetic profile characterized by a peak plasma concentration occurring within a few hours post-dose. It is extensively metabolized in the liver, primarily via CYP3A4, and is eliminated mainly through fecal excretion. The half-life of paritaprevir allows for once-daily dosing when used in combination therapies.

Pregnancy

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

Breast-feeding

It is unknown if paritaprevir is excreted in human milk. Caution is advised when administered to breastfeeding women.

Storage

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

Dosage

Children: Refer to specific pediatric dosing guidelines based on the identified drug, as 'hard' does not provide sufficient information.

Adults: Refer to specific drug information for dosing guidelines, as 'hard' does not specify a particular medication.

Mechanism of action

The mechanism of action for drugs termed 'hard' must be specified for accurate information, as this phrase does not designate a specific compound. Mechanisms may involve receptor interaction, enzyme inhibition, or modulation of biochemical pathways, depending on the drug in question. For example, opioid analgesics work primarily by binding to mu-opioid receptors in the central nervous system, leading to analgesic effects.

Pharmacodynamics

Pharmacodynamics refers to the effects of a drug on the body and its mechanisms of action. The pharmacodynamics of any drug classified as 'hard' would depend on its specific pharmacological profile, including its efficacy, potency, and the nature of its therapeutic effects. For instance, in the case of opioids, pharmacodynamic effects include pain relief, sedation, and potential respiratory depression.

Pharmacokinetics

Pharmacokinetics involves the absorption, distribution, metabolism, and excretion (ADME) of a drug. The pharmacokinetics of a substance termed 'hard' would vary significantly based on the specific drug. For many medications, absorption may occur via oral or parenteral routes, distribution may involve binding to plasma proteins, metabolism may occur in the liver, and excretion is typically renal. Each of these parameters is critical for understanding the drug's action and potential side effects.

Pregnancy

Consult a healthcare professional before use, as safety has not been established.

Breast-feeding

Consult a healthcare professional before use, as safety has not been established.

Storage

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

Indications

• Calcium deficiency
• Osteoporosis prevention
• Osteomalacia
• Rickets
• Paget's disease
• Hypoparathyroidism

Dosage

Children: Refer to specific product guidelines or consult a healthcare professional for appropriate dosing.

Adults: Refer to specific product guidelines or consult a healthcare professional for appropriate dosing.

Mechanism of action

The calcium carbonate found in shells acts as a calcium supplement, which is essential for many physiological functions, including bone formation and maintenance. It provides the necessary calcium ions that play a critical role in various cellular processes, including muscle contraction, neurotransmitter release, and blood coagulation.

Pharmacodynamics

Calcium carbonate is a source of calcium, a vital mineral that maintains bone density and overall bone health. When ingested, it dissociates in the stomach, releasing calcium ions that are absorbed in the intestines. It contributes to the prevention of osteoporosis and can aid in the treatment of calcium deficiencies. The effectiveness of calcium carbonate is influenced by factors such as the presence of food in the stomach, which may enhance its absorption.

Pharmacokinetics

After oral administration, calcium carbonate is dissolved in gastric acid and then absorbed primarily in the small intestine. The rate of absorption can be affected by the presence of food. The peak plasma concentration of calcium typically occurs within 1 to 3 hours post-ingestion. The elimination half-life of calcium varies, as it is stored in the bones and slowly released back into circulation. The body regulates calcium levels through hormonal control involving parathyroid hormone and calcitonin.

Pregnancy

Consult a healthcare provider for guidance, as safety during pregnancy may vary based on specific shellfish.

Breast-feeding

Consult a healthcare provider for guidance, as safety during breastfeeding may vary based on specific shellfish.

Storage

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

Dosage

Children: Refer to the specific drug's prescribing information for paediatric dosing guidelines.

Adults: Refer to the specific drug's prescribing information for adult dosing guidelines.

Mechanism of action

The mechanism of action would depend on the specific drug referred to by 'size'. Generally, drugs exert their effects through interaction with biological targets such as receptors, enzymes, or ion channels, leading to a physiological response.

Pharmacodynamics

Pharmacodynamics refers to the effects of the drug on the body, including the relationship between drug concentration and effect. This can involve receptor binding, signal transduction, and the resulting biological effects. Specific dynamics would vary based on the drug in question.

Pharmacokinetics

Pharmacokinetics describes the absorption, distribution, metabolism, and excretion (ADME) of a drug. Factors such as bioavailability, volume of distribution, half-life, and clearance would vary significantly based on the specific drug being considered.

Pregnancy

Safety in pregnancy has not been established. Use only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

Use with caution, as it is not known whether it is excreted in human milk.

Storage

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

Mechanism of action

Paritaprevir is a potent inhibitor of the NS3/4A serine protease of Hepatitis C Virus (HCV). Following viral replication of HCV genetic material and translation into a single polypeptide, Nonstructural Protein 3 (NS3) and its activating cofactor Nonstructural Protein 4A (NS4A) are responsible for cleaving it into the following structural and nonstructural proteins required for assembly into mature virus: NS3, NS4A, NS4B, NS5A, and NS5B. By inhibiting viral protease NS3/4A, paritaprevir therefore prevents viral replication and function.

Pharmacodynamics

At concentrations approximately 6 and 1.8 times the therapeutic concentrations of paritaprevir and ombitasvir, the combination did not prolong QTc to any clinically relevant extent.

Mechanism of action

As a PPI, lansoprazole is a prodrug and requires protonation via an acidic environment to become activated. Once protonated, lansoprazole is able to react with cysteine residues, specifically Cys813 and Cys321, on parietal H+,K+-ATPase resulting in stable disulfides. PPI's in general are able to provide prolonged inhibition of acid secretion due to their ability to bind covalently to their targets. Lansoprazole is a selective and irreversible proton pump inhibitor. In the acidic environment of the gastric parietal cell, lansoprazole is converted to active sulphenamide derivatives that bind to the sulfhydryl group of (H+, K+)-adenosine triphosphatase ((H+,K+)-ATPase), also known as the proton pump (H+,K+)-ATPase catalyzes the final step in the gastric acid secretion pathway. Lansoprazole's inhibition of (H+,K+)-ATPase results in inhibition of both centrally and peripherally mediated gastric acid secretion. The inhibitory effect is dose-related. Lansoprazole inhibits both basal and stimulated gastric acid secretion regardless of the stimulus.

Pharmacodynamics

Lansoprazole decreases gastric acid secretion by targeting H+,K+-ATPase, which is the enzyme that catalyzes the final step in the acid secretion pathway in parietal cells. Conveniently, lansoprazole administered any time of day is able to inhibit both daytime and nocturnal acid secretion. The result is that lansoprazole is effective at healing duodenal ulcers, reduces ulcer-related pain, and offers relief from symptoms of heartburn Lansoprazole also reduces pepsin secretion, making it a useful treatment option for hypersecretory conditions such as Zollinger-Ellison syndrome.