MAPIN INJECTION 0.4mg/ML

Product Information

Registration Status: Active

MAPIN INJECTION 0.4mg/ML is approved to be sold in Singapore with effective from 1998-10-23. It is marketed by DUOPHARMA (SINGAPORE) PTE LTD, with the registration number of SIN10290P.

This product contains Naloxone 0.4mg/ml in the form of INJECTION. It is approved for INTRAVENOUS, SUBCUTANEOUS, INTRAMUSCULAR use.

This product is manufactured by DUOPHARMA (M) SDN BHD in MALAYSIA.

It is a Prescription Only Medicine that can only be obtained from a doctor or a dentist, or a pharmacist with a prescription from a Singapore-registered doctor or dentist.

Naloxone

Description

Naloxone is an opioid antagonist medication used to block or reverse the effects of opioid drugs, particularly within the setting of drug overdoses which are rapidly becoming a leading cause of death worldwide. More specifically, naloxone has a high affinity for μ-opioid receptors, where it acts as an inverse agonist, causing the rapid removal of any other drugs bound to these receptors. When taken in large quantities, opioid medications such as morphine, hydromorphone, methadone, heroin, or fentanyl are capable of causing life-threatening symptoms such as respiratory depression, reduced heart rate, slurred speech, drowsiness, and constricted pupils. If untreated, this can progress to vomiting, absent pulse and breathing, loss of consciousness, and even death. Naloxone is indicated for the rapid reversal of these symptoms of central nervous system depression in opioid overdose. It's important to note that naloxone only works on opioid receptors within the body, and is therefore not capable of reversing the effects of non-opioid medications such as stimulants like methamphetamine or cocaine, or benzodiazepines like lorazepam or diazepam. Also known as the brand name product Narcan, naloxone is currently available by intramuscular (IM) or subcutaneous (SubQ) injection, nasal spray, or intravenous (IV) infusion. Naloxone IM injections are commonly available in the form of "kits", which is ideal for making overdose treatment accessible and readily available for administration by minimally trained individuals within the community. Kits commonly include the supplies necessary to treat an overdose in a non-medical setting such as alcohol swabs, syringes, a rescue breathing mask, and instructions for use. Frequently also carried by medical and emergency personnel and at events known to be associated with heavy drug use like music festivals, naloxone kits are considered a key component of harm reduction strategies. When injected intramuscularly (IM), naloxone acts within 3-5 minutes and can last from 30-60 minutes before its effects wear off. Administration of naloxone is associated with very few side effects. Notably, if injected into a person not currently using opioid medications, there would be no noticeable effects at all. However, for individuals using opioid medications or experiencing an overdose, IM injection of naloxone rapidly reverses opioid effects and can cause the injected individual to immediately experience withdrawal symptoms. Common symptoms of opioid withdrawal include nausea, vomiting, sweating, runny nose, aches, and diarrhea. Although certainly physically uncomfortable, opioid withdrawal symptoms are not life-threatening like they are for alcohol withdrawals. Administration of naloxone is therefore appropriate for any person appearing to have any symptoms of an opioid overdose. Due to its short duration of action, person's injected with naloxone should be monitored for responsiveness and potentially injected a second time or taken to the hospital. Naloxone is also available within the combination product Suboxone with the opioid medication buprenorphine. Suboxone is used for the maintentance treatment of opioid dependence and addiction. When taken orally, naloxone has no pharmacological effect and does not reduce the effectiveness of the opioid effect of buprenorphine. The primary purpose of including naloxone within Suboxone is to act as a deterrent to injection, as injected naloxone would rapidly reverse the effects of buprenorphine.

Indication

For the complete or partial reversal of narcotic depression, including respiratory depression, induced by opioids including natural and synthetic narcotics, propoxyphene, methadone and the narcotic-antagonist analgesics: nalbuphine, pentazocine and butorphanol. It is also indicated for the diagnosis of suspected acute opioid overdose. It may also be used as an adjunctive agent to increase blood pressure in the management of septic shock.

Mechanism of Action

While the mechanism of action of naloxone is not fully understood, the preponderance of evidence suggests that naloxone antagonizes the opioid effects by competing for the same receptor sites, especially the mu-opioid receptor. Recently, naloxone has been shown to bind all three opioid receptors (mu, kappa and gamma) but the strongest binding is to the mu receptor.

Pharmacokinetics

Absorption
Tmax: 0.4mg IM injection = 0.38 hr Nasal spray (one 2mg spray) = 0.33 hr Nasal spray (one 4mg spray) = 0.50 hr Cmax: 0.4mg IM injection = 0.88 ng/mL Nasal spray (one 2mg spray) = 2.91 ng/mL Nasal spray (one 4mg spray) = 4.83 ng/mL
Distribution
Following parenteral administration naloxone hydrochloride is rapidly distributed in the body. Naloxone is also very lipophillic and easily crosses the blood-brain-barrier. It can also cross the placenta.
Metabolism
Naloxone is hepatically metabolized and primarily undergoes glucuronidation to form naloxone-3-glucuronide.
Elimination

Toxicity

LD50, IV administration, mouse = 150 ± 5 mg/kg; LD50, IV administration, rat = 109 ± 4 mg/kg;

Active Ingredient/Synonyms

(−)-naloxone | 1-N-Allyl-14-hydroxynordihydromorphinone | 17-allyl-3,14-dihydroxy-4,5α-epoxymorphinan-6-one | Nalossone | Naloxona | Naloxone | Naloxonum | Naloxone |


Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.

References

  1. Health Science Authority of Singapore - Reclassified POM
  2. Drugbank