Cefarix 500

Indications

• Bacterial infections due to sensitive Gram-positive and Gram-negative bacteria
• Skin infections
• Soft-tissue infections
• Uncomplicated urinary-tract infections
• Acute diverticulitis (in combination with metronidazole)
• Prophylaxis of recurrent urinary-tract infections

Dosage

Children: Child 1 month–11 years: 25 mg/kg 2–4 times a day (max. per dose 500 mg). Child

Adults: 250 mg every 6 hours, alternatively 500 mg every 8–12 hours; increased to 1–1.5 g every 6–8 hours for severe infections.

Mechanism of action

Cefalexin inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins located in the bacterial cytoplasmic membrane. This action prevents the cross-linkage of peptidoglycan chains, which is essential for bacterial cell wall strength and rigidity. Consequently, this leads to cell lysis and death, particularly in rapidly dividing bacteria.

Pharmacodynamics

Cefalexin is bactericidal and exhibits activity primarily against Gram-positive bacteria. It is effective in treating superficial infections resulting from minor wounds or lacerations. By interfering with the cross-linking reaction between N-acetyl muramic acid and N-acetylglucosamine in the bacterial cell wall, cefalexin promotes cell lysis, making it a widely used antibiotic in clinical practice.

Pharmacokinetics

Cefalexin is well absorbed when taken orally, with peak plasma concentrations typically occurring within 1 hour of administration. It is widely distributed throughout body tissues and fluids, including bile, urine, and synovial fluid. The drug is primarily excreted unchanged in the urine, and its half-life is approximately 1 hour. Renal impairment may necessitate dosage adjustments.

Contra-indications

• Hypersensitivity to cephalosporins
• History of immediate hypersensitivity to penicillin and other beta-lactams

Adverse effects

• Abdominal pain
• Diarrhoea
• Dizziness
• Eosinophilia
• Headache
• Leucopenia
• Nausea
• Neutropenia
• Pseudomembranous enterocolitis
• Skin reactions
• Thrombocytopenia
• Vomiting
• Vulvovaginal candidiasis
• Anaphylactic reaction
• Angioedema
• Agranulocytosis
• Hemolytic anemia
• Tubulointerstitial nephritis
• Severe cutaneous adverse reactions (SCARs)

Interactions

• Probenecid may increase the serum concentration of cephalexin
• Antacids may decrease the absorption of cephalexin
• Other nephrotoxic drugs may increase the risk of kidney damage

Precautions

• Use with caution in patients with renal impairment
• Monitor for signs of superinfection during prolonged therapy
• Caution in patients with a history of gastrointestinal disease, particularly colitis

Pregnancy

Not known to be harmful.

Breast-feeding

Present in milk in low concentration, but generally considered appropriate to use.

Storage

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

Formulations

• Capsules: 250 mg, 500 mg
• Oral suspension: 125 mg/5 mL, 250 mg/5 mL

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

• Constipation
• Dietary fiber supplementation
• Irritable bowel syndrome
• Diverticular disease
• Weight management

Dosage

Children: Refer to appropriate guidelines for specific dosage; generally taken with adequate fluid intake.

Adults: Refer to appropriate guidelines for specific dosage; generally taken with adequate fluid intake.

Mechanism of action

Cellulose acts primarily as a bulk-forming laxative. It absorbs water in the intestines, which increases stool bulk and stimulates peristalsis, thus facilitating bowel movements. Additionally, cellulose is not digestible by human enzymes, leading to fermentation by gut bacteria, which may enhance gut health and alter gut microbiota composition.

Pharmacodynamics

Cellulose increases stool weight and frequency of bowel movements. It works by retaining water in the intestines, leading to softer stools and improved passage through the gastrointestinal tract. The bulking effect of cellulose can help alleviate constipation and promote overall digestive health. It may also play a role in cholesterol reduction and glycemic control through its effects on digestion and absorption of nutrients.

Pharmacokinetics

Cellulose is not absorbed into the bloodstream due to its indigestible nature. Instead, it passes through the gastrointestinal tract, where it adds bulk to the stool. Its fermentation by colonic bacteria produces short-chain fatty acids, which may have beneficial effects on colon health. The onset of action for cellulose as a laxative can vary but is generally within 24 to 72 hours after ingestion.

Adverse effects

• Bloating
• Flatulence
• Diarrhea
• Abdominal discomfort

Precautions

• Use with caution in patients with a history of gastrointestinal disorders.
• Monitor for potential allergic reactions in sensitive individuals.

Pregnancy

Cellulose is generally considered safe during pregnancy as it is a non-toxic, indigestible fiber.

Breast-feeding

Cellulose is also considered safe during breastfeeding; it is excreted in breast milk in negligible amounts.

Storage

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

Formulations

• Powder
• Capsules
• Tablets
• Granules

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

• Used as an excipient in tablet formulations
• Used as a bulking agent in capsule formulations
• Used in food products as a thickener or stabilizer

Dosage

Children: Refer to specific product guidelines as dosage will depend on the formulation and the active ingredients.

Adults: Refer to specific product guidelines as dosage will depend on the formulation and the active ingredients.

Mechanism of action

Microcrystalline cellulose acts as a non-digestible filler that enhances the flow properties of powders during the manufacturing of tablets and capsules. It does not have a direct pharmacological action on the body but ensures that the active ingredients are effectively delivered to the patient.

Pharmacodynamics

As a non-active ingredient, microcrystalline cellulose does not exert pharmacodynamic effects typical of active pharmaceutical ingredients. Its primary role is to provide a stable and consistent matrix for the drug, facilitating the release of the active compound once ingested.

Pharmacokinetics

Microcrystalline cellulose is not absorbed in the gastrointestinal tract; it passes through the digestive system largely unchanged. It adds bulk to the stool, which may aid in promoting regular bowel movements. The substance is excreted in feces, where it contributes to dietary fiber intake.

Pregnancy

Data regarding the use of microcrystalline cellulose during pregnancy is limited. It is advisable to consult with healthcare professionals before use.

Breast-feeding

Microcrystalline cellulose is considered safe during breastfeeding, as it is not absorbed systemically.

Storage

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

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

Cephalexin is a first generation cephalosporin antibiotic. Cephalosporins contain a beta lactam and dihydrothiazide. Unlike penicillins, cephalosprins are more resistant to the action of beta lactamase. Cephalexin inhibits bacterial cell wall synthesis, leading breakdown and eventualy cell death. CEPHALOTHIN & ITS CONGENERS INHIBIT BACTERIAL CELL-WALL SYNTHESIS IN MANNER SIMILAR TO THAT OF PENICILLIN. /CEPHALOSPORINS/ The penicillins and their metabolites are potent immunogens because of their ability to combine with proteins and act as haptens for acute antibody-mediated reactions. The most frequent (about 95 percent) or "major" determinant of penicillin allergy is the penicilloyl determinant produced by opening the beta-lactam ring of the penicillin. This allows linkage of the penicillin to protein at the amide group. "Minor" determinants (less frequent) are the other metabolites formed, including native penicillin and penicilloic acids. /Penicillins/ Bactericidal; action depends on ability to reach and bind penicillin-binding proteins located in bacterial cytoplasmic membranes; cephalosporins inhibit bacterial septum and cell wall synthesis, probably by acylation of membrane-bound transpeptidase enzymes. This prevents cross-linkage of peptidoglycan chains, which is necessary for bacterial cell wall strength and rigidity. Also, cell division and growth are inhibited, and lysis and elongation of susceptible bacteria frequently occur. Rapidly dividing bacteria are those most susceptible to the action of cephalosporins. /Cephalosporins/ CEPHALOSPORIN C IS VERY RESISTANT TO ACTION OF PENICILLINASE, FOR WHICH IT IS BOTH COMPETITIVE & NONCOMPETITIVE INHIBITOR, DEPENDING ON SUBSTRATE TESTED... /CEPHALOSPORINS/

Pharmacodynamics

Cephalexin (also called Cefalexin) is a first generation cephalosporin antibiotic. It is one of the most widely prescribed antibiotics, often used for the treatment of superficial infections that result as complications of minor wounds or lacerations. It is effective against most gram-positive bacteria through its inihibition of the cross linking reaction between N-acetyl muramicacid and N-acetylglucosamine in the cell wall, leading to cell lysis.

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.