Mioflex
Mioflex Uses, Dosage, Side Effects, Food Interaction and all others data.
Suxamethonium is a muscle relaxant. It acts as a depolarizing neuromuscular blocker by imitating the action of acetylcholine at the neuromuscular junction. Suxamethonium acts on muscle type nicotinic receptors. Binding of Suxamethonium to the nicotinic acetylcholine receptor results in opening of the receptor's nicotinic sodium channel; sodium moves into the cell, a disorganized depolarization of the motor-end plate occurs and calcium is released from the sarcoplasmic reticulum. This results in fasciculation. In the normal muscle, following depolarization, acetylcholine is rapidly hydrolyzed by acetylcholinesterase and the muscle cell is able to 'reset' ready for the next signal. But Suxamethonium is degraded not by acetylcholinesterase, rather by butyrylcholinesterase, a plasma cholinesterase. This hydrolysis by butyrylcholinesterase is much slower than that of acetylcholine by acetylcholinesterase. Thus Suxamethonium has a longer duration of effect than acetylcholine and it does not allow the muscle cell to 'reset' and keeps the 'new' resting membrane potential below threshold. When acetylcholine binds to an already depolarized receptor it cannot cause further depolarization. Calcium is removed from the muscle cell cytosol independent of repolarization. As the calcium is taken up by the sarcoplasmic reticulum, the muscle relaxes. This explains muscle flaccidity rather than tetany following fasciculation.
Mioflex's neuromuscular blockade takes effect within 60 seconds of intravenous administration and lasts between four to six minutes. Similar to acetylcholine, it binds to cholinergic receptors of the motor endplate to induce membrane depolarization and, eventually, muscle paralysis, which may be maintained for as long as an adequate concentration of succinylcholine remains at the receptor site. Mioflex has no direct action on smooth or cardiac muscle, nor does it appear to act on pre-synaptic or ganglionic acetylcholine receptors. The paralysis induced by succinylcholine has been described as "progressive", first involving the muscles of the face and glottis, then the intercostals and diaphragm, then followed by other skeletal muscles.
Mioflex has no effect on consciousness or pain threshold, and must therefore be used in conjunction with adequate anesthesia. There have been rare reports of the development of acute rhabdomyolysis with hyperkalemia - resulting in ventricular dysrhythmias, cardiac arrest, and death - after the intravenous administration of succinylcholine to apparently healthy pediatric patients who were subsequently found to have undiagnosed skeletal myopathy (most frequently Duchenne's muscular dystrophy). Infants or children experiencing seemingly idiopathic cardiac arrest soon after the administration of succinylcholine should therefore be treated immediately for hyperkalemia. Given that patients may not present with any apparent risk factors, the use of succinylcholine in pediatric patients should be restricted to emergency intubation or other situations in which a suitable alternative is unavailable.
| Trade Name | Mioflex |
| Availability | Prescription only |
| Generic | Succinylcholine |
| Succinylcholine Other Names | Dicholine succinate, Succinocholine, Succinoylcholine, Succinylbischoline, Succinyldicholine, Suxamethonium |
| Related Drugs | fentanyl, lidocaine, ketamine, hyoscyamine, propofol, glycopyrrolate |
| Weight | 50mg/ml, |
| Type | Injection |
| Formula | C14H30N2O4 |
| Weight | Average: 290.399 Monoisotopic: 290.220557458 |
| Groups | Approved |
| Therapeutic Class | Depolarizing muscle relaxants |
| Manufacturer | Usmanco International |
| Available Country | Pakistan, |
| Last Updated: | September 19, 2023 at 7:00 am |
Uses
Suxamethonium Chloride is a short-acting depolarizing neuromuscular blocking agent. It is used in anesthesia as a muscle relaxant to-
- Facilitate endotracheal intubation
- Aid in mechanical ventilation and
- Assist a wide range of surgical and obstetric procedures
Mioflex is also used to associated treatment for these conditions: Tracheal Intubation
How Mioflex works
Mioflex is a depolarizing neuromuscular blocker, meaning it causes a prolonged period of membrane depolarization in order to exert its therapeutic effects. It binds to the post-synaptic cholinergic receptors found on motor endplates, thereby inducing first transient fasciculations followed by skeletal muscle paralysis.
Dosage
Mioflex dosage
Suxamethonium Chloride is usually administered by bolus Intravenous or Intramuscular injection.
Adults: The dose of Suxamethonium is dependent on body weight, the degree of muscular relaxation required, the route of administration and the response of individual patients. To achieve endotracheal intubation Suxamethonium is usually administered intravenously in a dose of 1 mg/kg. This dose will usually produce muscular relaxation in about 30-60 seconds and has a duration of action of about 2-6 minutes. Supplementary doses of Suxamethonium of 50%-100% of the initial dose administered at 5-10 minutes intervals will maintain muscle relaxation during short surgical procedures performed under general anesthesia. For prolonged surgical procedures Suxamethonium may be given by intravenous infusion as a 0.1 %-0.2% solution, diluted in 5 % glucose solution or sterile isotonic saline solution, at a rate of 2.5 to 4 mg per minute. The infusion rate should be adjusted according to the response of individual patients. The total dose of Suxamethonium given by repeated intravenous injection or continuous infusion should not be exceeded 500 mg per hour.
Children: Infants and young children are more resistant to Suxamethonium compared with adults. The recommended intravenous dose of Suxamethonium for infants is 2 mg/kg. A dose of 1 mg/kg in older children is recommended. When Suxamethonium is given as intravenous infusion in children, the dosage is as for adults with a proportionately lower initial Infusion rate based on body weight. Suxamethonium may be given intramuscularly to infants at doses up to 4-5 mg/kg and in older children up to 4 mg/kg. These doses produce muscular relaxation within about 3 minutes. A total dose of 150 mg should not be exceeded.
Side Effects
Cardiovascular: bradycardia, tachycardia, hypertension, hypotension, arrhythmias.
Respiratory: bronchospasm, prolonged respiratory depression and apnea.
Musculoskeletal: muscle fasciculation, post-operative muscle pains, myoglobinemia.
Others: hyperthermia, increased intra-ocular pressure increased intra-gastric pressure, rash, excessive salivation.
Toxicity
Overdosage of succinylcholine is likely to extend the neuromuscular blockade beyond the time needed for surgery. Symptoms are likely to be consistent with its therapeutic effects, although more pronounced, and may therefore include skeletal muscle weakness, decreased respiratory reserve, low tidal volume, or apnea. Treatment of succinylcholine overdose involves airway and respiratory support until recovery of normal respiration is assured.
Depending on the extent of the overdose, the characteristic depolarizing (i.e. Phase I) neuromuscular blockade may switch to resemble more closely a non-depolarizing (i.e. Phase II) neuromuscular blockade. This occurs primarily when succinylcholine is given over a prolonged period of time or with particularly large doses, and may result in significant respiratory muscle paralysis or weakness.
Precaution
Suxamethonium should be administered only by or under close supervision of an anesthetist familiar with its action, characteristics and hazards, who is skilled in the management of artificial respiration and only where there are adequate facilities for immediate endotracheal intubation with administration of oxygen by intermittent positive pressure ventilation. The elderly may be more susceptible to cardiac arrhythmias, especially if digitalis-like drugs are also being taken.
Interaction
Certain drugs or chemicals are known to reduce normal plasma cholinesterase activity and may therefore prolong the neuromuscular blocking effects of Suxamethonium. These include: trimetaphan; specific anticholinesterase agents: neostigmine, pyridostigmine, physostigmine; cytotoxic compounds: cyclophosphamide, mechlorethamine, triethylene-melamine; psychiatric drugs: promazine and chlorpromazine, anesthetic agents and drugs: ketamine, morphine and morphine antagonists, pethidine, pancuronium.
Food Interaction
No interactions found.Mioflex Drug Interaction
Moderate: diltiazem, furosemideMinor: lorazepam, diazepam, midazolamUnknown: epinephrine, ipratropium, diphenhydramine, dexamethasone, glucose, hydromorphone, haloperidol, norepinephrine, pregabalin, naloxone, promethazine, clopidogrel, methylprednisolone, ketorolac, ondansetron
Mioflex Disease Interaction
Major: histamine release, pulmonary impair, burns, hyperkalemia, malignant hyperthermia, skeletal muscle myopathies, upper motor neuron injuryModerate: bradycardia, glaucoma, myasthenia gravis
Volume of Distribution
At intravenous doses of 1 mg/kg and 2 mg/kg in 14 patients, the mean apparent volumes of distribution were 16.4 ± 14.7 and 5.6 ± 6.8 mL/kg, respectively.
Half Life
The mean half-life of elimination following intravenous administration is 47 seconds.
Clearance
The mean in vivo plasma clearance of succinylcholine following an intravenous dose of 1 mg/kg in 18 patients was approximately 4.17 ± 2.37 L/min.
Elimination Route
Approximately 10% of an administered dose is excreted unchanged in the urine.
Pregnancy & Breastfeeding use
Although Suxamethonium does not readily cross the placental barrier it should not be administered to pregnant women unless the potential benefit outweighs possible hazards.
Contraindication
Suxamethonium has no effect on the level of consciousness and should not be administered to a patient who is notfullyanesthetized. Suxamethonium should not be administered to patients known to be hypersensitive to the drug. Suxamethonium is contraindicated in patients known to have an inherited atypical plasma cholinesterase activity. An acute transient rise in serum potassium often occurs following the administration of Suxamethonium in normal individuals (usually 0.5 mmol/Litre). But in certain pathological states it may cause excessive increase in serum potassium leading to serious cardiac arrhythmias and cardiac arrest. For this reason, use of Suxamethonium is contraindicated in patients recovering from major trauma, patients recovering from severe burns, patients with neurological deficits involving acute major muscle wasting and patients with pre-existing hyperkalemia. Suxamethonium causes a slight transient rise in intra-ocular pressure, and should therefore not be used in the presence of open eye injuries. The injection is contraindicated in new-born infants, especially in immature neonates.
Storage Condition
Store in a refrigerator between 2°-8° C. Do not freeze.
Innovators Monograph
You find simplified version here Mioflex
Mioflex contains Succinylcholine see full prescribing information from innovator Mioflex Monograph, Mioflex MSDS, Mioflex FDA label
FAQ
What is Mioflex used for?
Mioflex is a skeletal muscle relaxant for intravenous (IV) administration indicated as an adjunct to general anesthesia, to facilitate tracheal intubation, and to provide skeletal muscle relaxation during surgery or mechanical ventilation.
How safe is Mioflex?
Mioflex administration has been associated with acute onset of malignant hyperthermia, a potentially fatal hypermetabolic state of skeletal muscle. The risk of developing malignant hyperthermia following Mioflex administration increases with the concomitant administration of volatile anesthetics.
How does Mioflex work?
Mioflex is a depolarizing skeletal muscle relaxant. As does acetylcholine, it combines with the cholinergic receptors of the motor end plate to produce depolarization.
What are the common side effects of Mioflex?
Common side effects of Mioflex are include:
- Jaw rigidity.
- Low blood pressure (hypotension)
- Muscle fasciculation may result in postoperative pain.
- Muscle relaxation resulting in respiratory depression to the point of breathing cessation (apnea)
- Respiratory depression.
- Salivary gland enlargement.
Is Mioflex safe during pregnancy?
Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.
Is Mioflex safe during breastfeeding?
No information is available on the use of Mioflex during breastfeeding. Because it is rapidly eliminated and poorly absorbed orally, it is not likely to reach the bloodstream of the infant or cause any adverse effects in breastfed infants.
Can I drink alcohol with Mioflex?
The risk or severity of adverse effects can be increased when Mioflex is combined with Benzyl alcohol. The risk or severity of hyperkalemia can be increased when Mioflex is combined with Bepridil.
When should Mioflex be administered?
Mioflex should be used only by those skilled in the management of artificial respiration and only when facilities are instantly available for tracheal intubation and for providing adequate ventilation of the patient,
How long does it take for Mioflex to take effect?
The onset of effect of Mioflex given intramuscularly is usually observed in about 2 to 3 minutes.
When should I not take Mioflex?
Mioflex is contraindicated in patients after the acute phase of injury after major burns, multiple trauma, extensive denervation of skeletal muscle, or upper motor neuron injury.
How long does it take Mioflex to work?
The onset of effect of Mioflex given intramuscularly is usually observed in about 2 to 3 minutes.
Does Mioflex release histamine?
As with other neuromuscular blocking agents, the potential for releasing histamine is present following Mioflex administration.
What happens if I drink Mioflex ?
In emergency departments, intoxication with the muscle relaxant Mioflex often leads to a potentially lethal respiratory paralysis or other deleterious side effects.
Who should not take Mioflex?
Mioflex is contraindicated in persons with personal or familial history of malignant hyperthermia, skeletal muscle myopathies, and known hypersensitivity to the Mioflex.
Does Mioflex cause hypotension?
Common side effects of Mioflex are Low blood pressure (hypotension) Muscle fasciculation may result in postoperative pain.
Can Mioflex be reversed?
Mioflex can reverse profound blockade and can be given for immediate reversal and its use would avoid the potentially serious adverse effects of the currently used agent, Mioflex.
How long does it take for Mioflex to wear off?
Mioflex has been traditionally used as a first-line paralytic due to its quick onset of action and short half-life. Mioflex duration of action is 10,15 minutes, whereas the half-life of rocuronium is anywhere from 30,90 minutes, depending on the dose.
Can I take overdose of Mioflex?
If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
