1. Clinical Overview
Edaravone is a potent, synthetic, lipophilic free radical scavenger and antioxidant. It is a pyrazolone derivative specifically indicated for the treatment of Amyotrophic Lateral Sclerosis (ALS) and acute ischemic stroke. In the Indian context, its primary approved use is for ALS, where it is believed to slow the decline in physical function by mitigating oxidative stress, a key contributor to motor neuron degeneration. It is administered as a slow intravenous infusion.
| Onset | Duration | Bioavailability |
|---|---|---|
| Pharmacological effects begin during infusion, but clinical benefits in ALS are observed over weeks to months of treatment. | The pharmacological effect is transient, necessitating repeated dosing. The clinical treatment effect in ALS is sustained over the course of the cyclical treatment regimen. | 100% for intravenous administration. |
2. Mechanism of Action
Edaravone exerts its neuroprotective effects by scavenging a variety of free radicals, including hydroxyl radicals, peroxyl radicals, and peroxynitrite. In ALS, oxidative stress is implicated in the pathogenesis of motor neuron injury. By inhibiting lipid peroxidation and reducing oxidative damage to vascular endothelial cells and neuronal cells, edaravone is believed to slow the progression of functional decline.
3. Indications & Uses
- Amyotrophic Lateral Sclerosis (ALS)
4. Dosage & Administration
Adult Dosage: For ALS: 60 mg (i.e., 40 mL of the 1.5 mg/mL solution) administered as a 60-minute intravenous infusion once daily. Treatment is cyclical: Initial cycle: daily for 14 days, followed by a 14-day drug-free period. Subsequent cycles: daily for 10 days out of 14-day periods, followed by 14-day drug-free periods.
Administration: Must be diluted before infusion. Withdraw 40 mL (60 mg) of edaravone injection (1.5 mg/mL) and add to 100 mL of 0.9% Sodium Chloride Injection, USP. Administer via controlled intravenous infusion pump over 60 minutes. Do not mix with other medications. Inspect for particulate matter and discoloration before use. Use immediately after preparation.
5. Side Effects
Common side effects may include:
- Contusion
- Gait disturbance
- Headache
- Dermatitis
- Eczema
- Fatigue
- Increased blood creatine phosphokinase (CPK)
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| Sulfonamides (e.g., Cotrimoxazole) | Increased risk of hypersensitivity reactions due to shared sulfite/sulfa moiety. Potential for cross-reactivity. | Major |
| Other drugs containing sulfites (e.g., some epinephrine, dopamine injections) | Increased risk of sulfite-induced allergic reactions. | Moderate |
| Strong UGT inducers (e.g., Rifampicin, Carbamazepine, Phenytoin) | May increase the metabolism of edaravone, potentially reducing its efficacy. | Moderate |
| Nephrotoxic drugs (e.g., Aminoglycosides, NSAIDs, Vancomycin) | Additive risk of renal impairment. | Moderate |
| Hepatotoxic drugs (e.g., Paracetamol high dose, Statins, Azole antifungals) | Additive risk of hepatic injury. | Moderate |
7. Patient Counselling
- Do inform all healthcare providers about all medications you are taking.
- Do report any history of asthma, allergies, or kidney/liver problems before starting treatment.
- Do keep all scheduled infusion appointments for the cyclical therapy to be effective.
- Don't stop or change the treatment schedule without consulting your neurologist.
- Don't receive the infusion if the solution is discolored or contains particles.
8. Toxicology & Storage
Overdose: Limited data. Symptoms may be an extension of pharmacological effects and could include severe hypersensitivity reactions, acute renal failure, hepatic injury, and CNS effects like severe headache or dizziness.
Storage: Store the vials in their original carton at a temperature not exceeding 30°C. Protect from light. Do not freeze. After dilution in 0.9% Sodium Chloride, use immediately. Discard any unused portion. Keep out of reach of children.