Name: Ryanodex

Before Using Ryanodex

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:


Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.


Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of dantrolene in children.


Although appropriate studies on the relationship of age to the effects of dantrolene have not been performed in the geriatric patient, no geriatric-specific problems have been documented to date. However, elderly patients are more likely to have age-related kidney, liver, or heart problems, which may require caution in patients receiving dantrolene.


Pregnancy Category Explanation
All Trimesters C Animal studies have shown an adverse effect and there are no adequate studies in pregnant women OR no animal studies have been conducted and there are no adequate studies in pregnant women.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are receiving this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Alprazolam
  • Amlodipine
  • Amobarbital
  • Aprobarbital
  • Butabarbital
  • Butalbital
  • Carisoprodol
  • Chloral Hydrate
  • Chlordiazepoxide
  • Chlorzoxazone
  • Cinnarizine
  • Clevidipine
  • Clobazam
  • Clonazepam
  • Clorazepate
  • Dantrolene
  • Diazepam
  • Diltiazem
  • Estazolam
  • Ethchlorvynol
  • Felodipine
  • Flunitrazepam
  • Flurazepam
  • Halazepam
  • Isradipine
  • Ketazolam
  • Lorazepam
  • Lormetazepam
  • Medazepam
  • Mephenesin
  • Mephobarbital
  • Meprobamate
  • Metaxalone
  • Methocarbamol
  • Methohexital
  • Methotrexate
  • Midazolam
  • Nicardipine
  • Nifedipine
  • Nimodipine
  • Nisoldipine
  • Nitrazepam
  • Oxazepam
  • Pentobarbital
  • Phenobarbital
  • Prazepam
  • Primidone
  • Quazepam
  • Secobarbital
  • Sodium Oxybate
  • Temazepam
  • Thiopental
  • Triazolam
  • Verapamil

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Precautions While Using Ryanodex

Your doctor will only give you a few doses of this medicine until your condition improves, and then you will be switched to an oral medicine that works the same way. If you have any concerns about this, talk to your doctor.

This medicine may cause drowsiness, dizziness, or muscle weakness in some people. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or are not alert or well-coordinated.

Ryanodex Dosage and Administration

Dosage for Treatment of Malignant Hyperthermia

In addition to Ryanodex treatment, institute the following supportive measures:

  • Discontinue use of malignant hyperthermia (MH)-triggering anesthetic agents (i.e., volatile anesthetic gases and succinylcholine).
  • Manage the metabolic acidosis
  • Institute cooling when necessary
  • Administer diuretics to prevent late kidney injury due to myoglobinuria (the amount of mannitol in Ryanodex is insufficient to maintain diuresis) [see Description (11)]

Administer Ryanodex by intravenous push at a minimum dose of 1 mg/kg. If the physiologic and metabolic abnormalities of MH continue, administer additional intravenous boluses up to the maximum cumulative dosage of 10 mg/kg.

If the physiologic and metabolic abnormalities reappear, repeat Ryanodex dosing by intravenous push starting with 1 mg/kg.

Dosage for Prevention of Malignant Hyperthermia

The recommended prophylactic dose of Ryanodex is 2.5 mg/kg administered intravenously over a period of at least 1 minute, starting approximately 75 minutes prior to surgery. Avoid agents that trigger MH.

If surgery is prolonged, administer additional individualized Ryanodex doses during anesthesia and surgery [see Clinical Pharmacology (12.3)].

Dosage for Pediatric Patients

The recommended weight-based dose of Ryanodex for pediatric patients in the treatment and prevention of MH is the same as for adults for these indications [see Dosage and Administration (2.1, 2.2)].

Reconstitution and Administration Instructions

The supplied lyophilized powder must be reconstituted prior to administration:

(a) Reconstitute each vial of Ryanodex lyophilized powder by adding 5 mL of sterile water for injection (without a bacteriostatic agent). Do not reconstitute with any other solution (e.g., 5% dextrose injection, 0.9% sodium chloride injection). (b) Shake the vial to ensure an orange-colored uniform suspension. Visually inspect the vial for particulate matter and discoloration prior to administration. (c) Must use the contents of the vial within 6 hours after reconstitution. Store reconstituted suspensions at controlled room temperature (68°F to 77°F or 20°C to 25°C).

Do not dilute or transfer the reconstituted Ryanodex suspension to another container to infuse the product.

Administer the reconstituted Ryanodex suspension either:

  • Into the intravenous catheter while an intravenous infusion of 0.9% sodium chloride injection, or 5% dextrose injection is freely running; or
  • Into the indwelling catheter - after assuring its patency - without a freely running infusion. Flush the line to assure that there is no residual Ryanodex remaining in the catheter [see Warnings and Precautions (5.3)].

Dosage Forms and Strengths

For injectable suspension: Ryanodex is a sterile, lyophilized powder containing 250 mg of dantrolene sodium for reconstitution, in single use vials

Patient Counseling Information

Inform patients, their families, or their caregivers of the following:

Muscle Weakness

Muscle weakness (i.e., decrease in grip strength and weakness of leg muscles, especially walking down stairs) is likely to occur with the use of Ryanodex. Patients should be provided assistance with standing and walking until their strength has returned to normal [see Warnings and Precautions (5.1)].

Difficulty Swallowing

Caution is indicated at meals on the day of administration because difficulty swallowing and choking have occurred with the use of dantrolene sodium products in general; dysphagia has been reported with the use of Ryanodex [see Warnings and Precautions (5.1)].

Dizziness and Somnolence

The use of Ryanodex has been associated with dizziness and somnolence. [see Warnings and Precautions (5.2)].

Driving or Operating Machinery

Symptoms such as “lightheadedness” may occur. Since some of these symptoms may persist for up to 48 hours, patients must not operate an automobile or engage in other hazardous activity during this time [see Warnings and Precautions (5.2)].

Marketed by:
Eagle Pharmaceuticals, Inc.
Woodcliff Lake, NJ 07677