ZINRO

Indications

• Adjustment of pH in pharmaceutical formulations
• Facilitation of drug absorption
• Used in sterile preparations

Dosage

Children: Refer to specific product guidelines for dosing information, as hydrochloric acid is typically used in a controlled setting based on formulation requirements.

Adults: Refer to specific product guidelines for dosing information, as hydrochloric acid is typically used in a controlled setting based on formulation requirements.

Mechanism of action

Hydrochloric acid dissociates in aqueous solution to release hydrogen ions (H+), leading to a decrease in pH. This acidic environment promotes the activation of pepsinogen to pepsin, an enzyme essential for protein digestion. Additionally, the acidity aids in the absorption of certain minerals and drugs that require an acidic environment for optimal bioavailability.

Pharmacodynamics

The primary pharmacodynamic action of hydrochloric acid is the maintenance of gastric acidity, which is essential for normal digestive processes. The acidic environment helps in denaturing proteins, activating digestive enzymes, and providing a barrier against pathogenic microorganisms. Its effects can influence the absorption and efficacy of various medications, particularly those that are pH-dependent.

Pharmacokinetics

Hydrochloric acid does not undergo significant systemic absorption when used in its normal contexts, as it acts locally within the gastrointestinal tract. The amount of hydrochloric acid produced by the stomach varies with food intake and physiological needs. It is secreted by parietal cells in the gastric mucosa, and its secretion is regulated by neural, hormonal, and local factors. The half-life of hydrochloric acid is not applicable as it is continuously produced and neutralized within the gastrointestinal tract.

Contra-indications

• Hypersensitivity to hydrochloric acid or any of its components
• Severe renal impairment
• Active gastrointestinal bleeding

Adverse effects

• Abdominal pain
• Diarrhea
• Nausea
• Vomiting
• Esophageal irritation
• Gastric mucosal irritation
• Electrolyte imbalances

Interactions

• May interact with alkaline substances, potentially neutralizing hydrochloric acid
• Caution with antacids as they may affect the efficacy of hydrochloric acid

Precautions

• Use with caution in patients with a history of gastritis or gastric ulcers
• Monitor electrolytes in prolonged use
• Use cautiously in patients with respiratory conditions due to potential aspiration risks

Pregnancy

Hydrochloric acid is classified as a category C drug. Use during pregnancy only if clearly needed and the potential benefits justify the risks to the fetus.

Breast-feeding

There is limited data on the excretion of hydrochloric acid in human milk. Use with caution during breastfeeding.

Storage

Store in a cool, dry place away from direct sunlight and heat. Ensure the container is tightly closed.

Formulations

• Oral solutions
• Injectable forms
• Tablets

Dosage

Children: Refer to specific guidelines for pediatric dosing; consult the BNF for Children for accurate dosage information.

Adults: Refer to specific guidelines for use; dosage may vary based on the context of use.

Mechanism of action

Hydroxide ions act primarily as bases, neutralizing acids to form water and salts. They participate in various biochemical pathways, including selenium metabolism and the degradation of reactive oxygen species. Hydroxide can influence enzyme activity and stability by altering the pH of the environment, thereby affecting metabolic reactions.

Pharmacodynamics

Hydroxide ions can impact biological processes by changing the local pH, which influences enzyme activity, ion transport, and the solubility of other compounds. Their ability to neutralize acids can help regulate physiological pH, contributing to homeostasis in living organisms.

Pharmacokinetics

As an inorganic ion, hydroxide does not undergo traditional pharmacokinetic processes like absorption, distribution, metabolism, or excretion. Instead, it is rapidly equilibrated in biological fluids and participates in acid-base reactions, having immediate effects on the local environment.

Pregnancy

There is limited information regarding the use of hydroxide during pregnancy. Consult a healthcare professional for advice.

Breast-feeding

Limited data is available on the excretion of hydroxide in breast milk. Consult a healthcare professional before use.

Storage

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

Indications

• Bacterial vaginosis
• Amoebiasis
• Giardiasis
• Trichomoniasis
• Infections caused by anaerobic bacteria

Dosage

Children: Dosing in children is determined based on weight and the specific indication. Refer to the BNF for Children for appropriate dosing guidelines.

Adults: The usual adult dose is 1.5 g orally once daily for 5 days for bacterial vaginosis or 1 g orally once daily for 3 days for amoebiasis. Refer to the BNF for specific indications and adjustments.

Mechanism of action

Ornidazole exerts its antimicrobial effects through the reduction of its nitro group by anaerobic bacteria and protozoa, resulting in the formation of reactive intermediates that interact with microbial DNA. This leads to the disruption of DNA synthesis and ultimately causes cell death. The drug's activity is primarily directed towards anaerobic organisms, including certain protozoa.

Pharmacodynamics

Ornidazole demonstrates a concentration-dependent bactericidal effect against susceptible organisms. Its activity is influenced by the reduction potential of the nitro group, which is crucial for its antimicrobial action. Ornidazole has a broad spectrum of activity, particularly against anaerobes and protozoa, and has been shown to be effective in both in vitro and in vivo models of infection.

Pharmacokinetics

Ornidazole is rapidly and completely absorbed following oral administration, achieving peak plasma concentrations within 1 to 3 hours. It is widely distributed throughout the body, including the central nervous system. The drug is metabolized mainly in the liver, with a half-life of approximately 8 to 10 hours. Excretion occurs primarily through the urine, with a small fraction eliminated unchanged.

Contra-indications

• Hypersensitivity to ornidazole or any of its components
• History of neurological disorders, particularly seizures

Adverse effects

• Nausea
• Vomiting
• Headache
• Dizziness
• Dry mouth
• Metallic taste
• Peripheral neuropathy

Interactions

• Alcohol: Concurrent use may lead to disulfiram-like reactions including flushing, tachycardia, and vomiting
• Anticoagulants: May enhance the effects of warfarin and other anticoagulants
• Other neurotoxic agents: Increased risk of neurological side effects

Precautions

• Use with caution in patients with a history of seizures
• Monitor liver function in patients with hepatic impairment
• Discontinue if neurological symptoms occur

Pregnancy

Ornidazole is not recommended during pregnancy unless the benefit outweighs the risk, particularly in the first trimester.

Breast-feeding

Ornidazole is excreted in breast milk, caution is advised when administering to nursing mothers.

Storage

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

Formulations

• Tablets: 500 mg
• Infusion: 100 mg/100 mL