dantrolene sodium hemiheptahydrate at a glance
Medicine class
Direct-acting skeletal muscle relaxant
Licensed use
Emergency treatment of malignant hyperthermia in adults and children
Administration
Prepared and injected into a vein by healthcare professionals
What is dantrolene sodium hemiheptahydrate used for?
This product is licensed for:
Treating malignant hyperthermia in adults and children alongside appropriate supportive measures.
How does dantrolene sodium hemiheptahydrate work?
It suppresses calcium release from storage sites inside skeletal muscle. This reduces excessive muscle contraction and the associated heat and metabolic disturbance.
dantrolene sodium hemiheptahydrate preparations and strengths
Injection
Route: Parenteral
Strengths: 120 mg
How to take dantrolene sodium hemiheptahydrate
This emergency treatment is not self-administered. Healthcare professionals prepare the powder with water for injections and give the resulting yellow-orange solution into a vein. It must not be injected into an artery or allowed to leak outside the vein.
Supportive treatment for malignant hyperthermia must continue alongside dantrolene.
Do not drive or operate machinery while muscle weakness, dizziness or light-headedness persists.
dantrolene sodium hemiheptahydrate side effects
Common or expected effects
- Muscle weakness is the most commonly reported effect after intravenous dantrolene; its precise frequency is unknown.
- Muscle fatigue, dizziness, drowsiness, headache, nausea, vomiting and injection-site reactions can occur.
Get urgent medical advice
- Severe allergic reaction, including breathing difficulty, swelling, light-headedness or loss of consciousness.
- Respiratory depression or failure, particularly with severe muscle weakness.
- Heart failure, abnormal heart rate or high blood potassium.
- Gastrointestinal bleeding or severe liver injury; reported liver failure has mainly been associated with prolonged oral treatment.
- Thrombophlebitis or tissue injury if the alkaline solution escapes from the vein.
dantrolene sodium hemiheptahydrate in pregnancy
Information in pregnancy is limited, and dantrolene crosses the placenta. It may be used when clinically necessary after weighing maternal and fetal risks. Uterine weakness and neonatal muscle weakness have been reported when intravenous dantrolene was given around caesarean birth.
dantrolene sodium hemiheptahydrate while breastfeeding
Dantrolene passes into breast milk, and a risk to the infant cannot be excluded. The product information advises interrupting breastfeeding during treatment. Support may be needed to maintain milk supply.
dantrolene sodium hemiheptahydrate interactions
Important interactions include:
Calcium-channel blockers, particularly verapamil or diltiazem
Combined use is not recommended because of potential heart failure and high blood potassium.
Non-depolarising muscle relaxants, such as vecuronium
Dantrolene may increase their muscle-relaxing effect and the risk of weakness or respiratory impairment.
Common questions about dantrolene sodium hemiheptahydrate
Answers are fully visible for fast scanning and source review.
Why is it used for malignant hyperthermia?
It reduces uncontrolled calcium release inside skeletal muscle, helping excessive muscle contraction, heat production and metabolic disturbance to settle.
Can children receive it?
Yes. This product is licensed for malignant hyperthermia in children and adults.
Does it replace cooling and supportive care?
No. Ventilatory, cooling and other appropriate supportive measures must continue alongside it.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.