Usage
Inosine pranobex is an antiviral and immunomodulatory agent. It is prescribed as an adjunct for various viral infections including:
- Mucocutaneous herpes simplex virus (HSV) infections (types 1 and 2): Used in conjunction with other treatments.
- Genital warts: As an adjunct to podophyllin or carbon dioxide laser therapy.
- Subacute sclerosing panencephalitis (SSPE): May help retard neurological deterioration.
Pharmacological Classification: Antiviral, immunomodulatory agent.
Mechanism of Action: Inosine pranobex has a dual mechanism:
- Enhances immune response: Stimulates T-lymphocyte and macrophage activity and influences cytokine production. This helps restore and normalize cell-mediated immunity.
- Direct antiviral effect: May inhibit viral replication by interfering with viral RNA and protein synthesis.
Alternate Names
- Inosine acedoben dimepranol
- Isoprinosine (Brand name)
- Methisoprinol (Brand name)
- Imunovir (Brand name)
- Groprinosin (Brand name)
- Isojol (Brand name)
- Primunovir (Brand Name)
- Inosiplex (Brand Name)
- Viruxan Forte (Brand Name)
- Viruxan Kids (Brand Name)
- Inosipranol (Brand Name)
How It Works
Pharmacodynamics: Inosine pranobex enhances cell-mediated immunity by stimulating T-lymphocyte differentiation and proliferation and increasing macrophage activity. It also modulates cytokine production, contributing to a balanced immune response. The drug’s direct antiviral effects may involve inhibition of viral RNA and protein synthesis.
Pharmacokinetics:
- Absorption: Rapidly absorbed from the gastrointestinal tract.
- Metabolism: Inosine is metabolized to uric acid. The p-acetamidobenzoic acid component is primarily metabolized to O-acylglucuronide, while N,N-dimethylamino-2-propanol is mainly metabolized to N,N-dimethylamino-2-propanol-N-oxide.
- Excretion: Metabolites are primarily excreted in the urine within 24 hours.
Mode of Action: Influences lymphocyte function, enhances cytokine production, and may directly affect viral RNA and protein synthesis.
Receptor binding, enzyme inhibition, neurotransmitter modulation: Specific details on receptor interactions or enzyme inhibition are not well-defined in the literature.
Dosage
Standard Dosage
Adults:
- 50-100 mg/kg/day, up to a maximum of 3-4 g/day, divided into 3-4 doses.
- Example: 1 gram (two 500 mg tablets) three to four times daily.
Children:
- 50 mg/kg/day, up to a maximum of 3-4 g/day, divided into 3-4 doses.
- Dosage may be adjusted based on weight and severity of the condition.
- For liquid formulations: 1 ml/kg per day in 3-4 divided doses
Special Cases:
- Elderly Patients: Close monitoring of uric acid levels and renal function is advised. Dose adjustment may be needed based on organ function.
- Patients with Renal Impairment: Use with caution and monitor uric acid levels. Dose reduction might be necessary.
- Patients with Hepatic Dysfunction: Close monitoring of liver function tests. Dose adjustment might be necessary.
- Patients with Comorbid Conditions (Gout, Hyperuricemia): Use cautiously as inosine pranobex increases uric acid levels. Close monitoring of uric acid levels essential.
Clinical Use Cases
The dosage guidelines provided above apply across clinical settings. Specific dosage recommendations for clinical cases like intubation, surgical procedures, mechanical ventilation, or ICU use may need to be individualized based on the patient’s specific situation and condition.
Dosage Adjustments:
Dose modifications based on renal/hepatic dysfunction, other metabolic disorders, or genetic variations need to be determined by the treating physician according to the patient’s condition.
Side Effects
Common Side Effects:
- Increased uric acid levels in blood and urine (usually transient).
- Nausea, vomiting
- Gastrointestinal discomfort
- Headache, dizziness
- Fatigue, malaise
- Pruritus, skin rash
Rare but Serious Side Effects:
- Allergic reactions (urticaria, angioedema, anaphylaxis).
- Liver dysfunction (elevated liver enzymes).
- Renal dysfunction
Long-Term Effects: Potential for ureteric or biliary calculi with prolonged use.
Contraindications
- Hypersensitivity to inosine pranobex or any component of the formulation.
- Gout or significantly elevated uric acid levels.
Drug Interactions
- Immunosuppressants: May reduce the efficacy of inosine pranobex.
- Other antiviral drugs: Could potentiate or diminish the overall antiviral effect.
- Uric acid-lowering drugs (allopurinol): Requires careful monitoring of uric acid levels.
- Drugs metabolized by the liver (some antiepileptics, statins): May require dosage adjustments due to potential for increased liver toxicity.
- Zidovudine: Inosine pranobex increases zidovudine plasma concentrations.
- Diuretics (e.g. Furosemide, Torsemide): Possible interactions.
- Uricosuric agents (e.g. Benzbromarone, Probenecid): Possible interactions.
Pregnancy and Breastfeeding
- Pregnancy Safety Category: Insufficient data in human studies. Animal studies show no adverse effects. Use with caution and only if potential benefits outweigh risks.
- Breastfeeding: Limited information on excretion into breast milk. Use cautiously and consider safer alternatives if necessary.
Drug Profile Summary
- Mechanism of Action: Immunomodulator; enhances T-cell and macrophage function and may inhibit viral replication.
- Side Effects: Elevated uric acid, nausea, GI discomfort, headache, rash, fatigue.
- Contraindications: Hypersensitivity, gout, elevated uric acid.
- Drug Interactions: Immunosuppressants, antivirals, uric acid-lowering agents, zidovudine.
- Pregnancy & Breastfeeding: Use with caution if benefits outweigh risks. Limited information on excretion into breastmilk.
- Dosage: 50-100 mg/kg/day divided into 3-4 doses; adjust for renal/hepatic impairment.
- Monitoring Parameters: Uric acid levels, liver function tests, renal function tests.
Popular Combinations
Inosine pranobex can be combined with other antivirals or other medications depending on the specific condition. However, the rationale for combinations must be carefully considered due to potential drug interactions.
Precautions
- Assess for hypersensitivity, gout, hyperuricemia, renal impairment before starting treatment.
- Monitor uric acid levels and renal function during treatment, especially in long-term use.
- In pregnancy, use only if benefits outweigh risks.
- For breastfeeding mothers, data is limited, consider safer alternatives.
- Pediatric and geriatric use requires careful dosing and monitoring.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Inosine pranobex?
A: The standard dosage for adults and children is 50-100 mg/kg/day, up to a maximum of 3-4 g/day, divided into 3-4 doses. Dose adjustments are required for patients with renal or hepatic impairment and those with gout/hyperuricemia.
Q2: What are the common side effects of Inosine pranobex?
A: Common side effects include increased uric acid levels, nausea, gastrointestinal discomfort, headache, dizziness, fatigue, and skin rash.
Q3: Is Inosine pranobex safe during pregnancy and breastfeeding?
A: Data regarding safety during pregnancy are limited. Use cautiously only if the benefits outweigh the potential risks. Similarly, limited data are available for breastfeeding. Monitor the infant for potential side effects.
Q4: How does Inosine pranobex interact with other medications?
A: It can interact with immunosuppressants, other antiviral drugs, medications affecting uric acid levels, and drugs metabolized by the liver. Always review concomitant medications for potential interactions.
Q5: Can Inosine pranobex be used in patients with renal or hepatic impairment?
A: Use with caution in these patient populations. Dose adjustments and close monitoring of organ function are essential.
Q6: What is the mechanism of action of Inosine pranobex?
A: It acts as both an antiviral and immunomodulatory agent. It may directly interfere with viral replication and stimulate the immune system by enhancing T-cell and macrophage function and cytokine production.
Q7: What are the contraindications for Inosine pranobex use?
A: Contraindications include hypersensitivity to the drug and pre-existing gout or severely elevated uric acid levels.
Q8: What are the long-term effects of taking Inosine pranobex?
A: Prolonged use may increase the risk of developing ureteric or biliary calculi (stones). Regular monitoring is necessary.
Q9: Can Inosine Pranobex be crushed and mixed with liquids or food?
A: Yes, tablets can be crushed and dissolved in a small amount of liquid or mixed with soft foods for easier administration, especially in children or patients who have difficulty swallowing tablets.
