Pharmacology: Morphine

Subject: Health Care
Type: Definition Essay
Pages: 12
Word count: 3065
Topics: Nursing, Drug Abuse, Medicine, Pharmacy
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Introduction

Morphine is a painkiller that is used to treat modest to severe pain (Weil & Rosen, 2004). Morphine is a narcotic analgesic, and its mode of action is on the Central Nervous System (CNS) (Jann et al, 2016). The drug can only be obtained on prescription from the doctor. In the United Kingdom, the drug is also known as MXL, morphgesic, zomorph, Sevredol, MST, and Oramorph. Morphine comes in the form of tablets, capsules, injections, suppositories, granules, and as a liquid that can be swallowed (Macintyre et al., 2006). Suppositories are used when swallowing, or injections are impossible. Morphine was selected because it is a commonly used, but it is also Controlled Drug; therefore, important guidelines must be followed in its ordering, storage, and disposal (NHS, 2008). Common side effects associated morphine include low blood pressure and respiratory suppression. Furthermore, the drug can become habitual, leading to abuse.   

This paper will review the use of morphine as a painkiller. First, the paper will explore the chosen drug by discussing its trade name, generic names, its functions and the reason the drug was selected.  It will be followed by an overview of how the drug is ordered, stored, and disposed of.  The next section will discuss the pharmacokinetics and pharmacodynamics of morphine. It will involve an exploration of how the drug acts on the body and how the body acts on the drug respectively. Next will be followed by an overview of Patient Group Directions (PGD) about morphine. Next, an evaluation of the legal and ethical frameworks that underpin the use of morphine will be conducted. Lastly, a discussion of morphine’s suitable for self-administration of medication (SAM). 

Ordering, Receiving, Storage, and Disposal of Morphine

Morphine is a controlled drug; therefore, specific policy guidelines must be followed in its procurement, storage, and disposal. Morphine must be ordered according to the recent Pharmacy Computer Stock Control guidelines for the ordering of medicines (NHS, 2008). This must be sanctioned by the Finance Department and outside auditors. Procurement of morphine is done by pharmacy staff, and other medical personnel is not involved in its purchase (NHS, 2008). Nurses ordering morphine must be qualified and knowledgeable in the critical processes needed to administer the drug. A Registered Nurse or any other competent employee, who must be a signatory for that section, can order morphine. Pharmacy staff can also order morphine into the ward, but they must be signatories to that clinical part.  Stationery used to order morphine into the ward are known as controlled stationery and are kept by the selected Registered Nurse or Manager in Charge. This stationery comprises Ward Drug Registers, Drug Order Books, Prescription Forms, and Emergency Requisition Forms (NHS, 2008). The appointed Registered Nurse is accountable for making sure that ordering practice is within the agreed schedule. This will ensure that doses are not missed, and drugs are not wasted.

Storage of morphine follows strict guidelines. At all times, the appointed nurse is accountable for making sure that morphine is kept in secure cupboards or lockable refrigerators. The locked cabinets must not be marked to show the contents inside. Morphine mist is stored properly to minimize errors when choosing the right formulation and maintain the desired quality. Additionally, it must be kept in a manner that ensures the labels remain legible (NHS, 2008). Morphine must also be separated into solid oral doses and liquid preparations to lower risk of choosing the incorrect preparation, and to promote efficient ordering and stock control (NHS, 2008). Since morphine can be administered through non-oral routes in the form of suppositories, it is important to separate these preparations to avoid the chances of wrong route administration. During storage, the morphine must be stored in the original packaging. Ampoules, blister packets, and vials must be kept in their original boxes during storage. It is also important to keep all cupboards or storage refrigerators locked when not being used. The appointed nurse must check the expiry date and rotate medications to ensure that older stock is used forts to avoid expiration. The designated nurse must always hold the keys to cupboards that hole morphine. The key to the cabinet must be separated from other keys and only given to authorized personnel when the medication is required. 

Morphine falls under Schedule 2 drugs, which means that it must be disposed of according to the Misuse of Drugs Act of 1971. Disposal of morphine can be carried in two ways. First, the drug can be destroyed within the hospital since it is licensed to use the drug (NHS, 2008). Morphine is destroyed by approved personnel, but it must be witnessed by an authorized individual. Secondly, it can be disposed of through a waste contractor. Unwanted or expired morphine can be disposed of by a licensed contractor who can transport and destroy the drugs. This contactor must be licensed by the home office to carry and witness the destruction of the drugs (William, 2007). Furthermore, the removal must be conducted in a facility that has the necessary waste management permit.

Pharmacokinetics

Absorption

Morphine is absorbed into the blood stream through different routes depending on the route of administration.  When swallowed orally in the form of capsules or tablets, it is absorbed through the gastrointestinal tract. It can also be delivered intravenously directly into the blood stream. This route is used mainly when the effects of the drug are requited fast (Macintyre et al., 2006). Suppositories can also be placed in the rectal area, which enables the drug to be absorbed through the rectal blood vessels. Alternatively, it can be delivered through injections into the subcutaneous layer. It will create a depot that enables the drug to be delivered into the blood stream. Additional routes of administration include injection into the spinal column or snorting in the form of order.

Distribution

The bioavailability of morphine is between 20% and 40 %, and 35% of this is bound to the plasma. Its half-life is between 1.5 and to 7 hours, which is relatively short (Szkutnik-Fiedler et al., 2014). Morphine is glucoro conjugated at positions three and six to produce morphine-3-gllucoronide and morphine-6-glucortonide. A small amount of 5 percent is demethylated to form normophine. Morphine-6-glucorinide is more potent compared to morphine, and it can accrue after prolonged administration or in persons with kidney problems. The half-life of morphine-6-glucorinide is between 2.5 and 5.5 hours (Szkutnik-Fiedler et al., 2014). Almost 90% of a single dose is excreted after 72 hours through the urine. 

Metabolism

Once in the blood stream, morphine is transported to the liver where it undergoes the first-pass metabolism. A significant amount of morphine is metabolized during this metabolism, which means that about 40 to 50 percent of morphine enters the central nervous system.  When injected through subcutaneous route, about 60 percent of morphine is converted onto morphone-3-glucotinide, while 10 percent is converted onto morphine-6-glucorinide. At phase II metabolism, morphine is glucuronidated by the enzyme UDP-glucuronosyl transferase-2B7 (Yousefpour et al., 2016).  Additionally, small quantities of morphine may be metabolized into normorphine, hydromorphone, and codeine. 

Excretion 

As noted earlier, about 90 percent of morphine is eliminated through urine within 24 hours of administration (Juul et al., 2016). Additionally, it can be stored in the form of fat; therefore, it is detectable for long periods of use and even when the individual is dead.

Pharmacodynamics

Morphine acts mainly on the Central Nervous System via m-Receptors, but it can also through k and d-Receptors. M1-receptors are responsible for pain management, respiratory depression, numbness, miosis, diminished gastrointestinal activity, and euphoria (Ravn et al., 2014). On the other hand, m2-revetpratke part in drowsiness, respiratory depression, mental clouding, and nausea. K-receptors take part in diuresis, analgesia, delusions, dysphoria, and hallucinations. The enzyme that is primarily involved in the metabolism of morphine is 5′-diphosphate-glucoronsyltransferase (UGT) 2B7 isoform (Setnik et al., 2014). The likely inhibitors of this enzyme cab lower the rate or elimination if taken concurrently. 

Alcohol enhances the CNS impacts of morphine such as drowsiness, sedation, and diminished motor skills. When used with other CNS depressants such as benzodiazepines, barbiturates, tricyclic antidepressants, MAO inhibitors, hypnotics, and antihistamines, the chances of respiratory depression, profound sedation, hypotension and even coma are increased. Morphine is also known to increase the neuromuscular blocking action of muscle relaxants and generate enhance levels of respiratory depression. Additionally, small doses of amphetamines are known to boost the analgesic and euphoric impacts of morphine and may lower its sedative effects. Partial antagonists such as nalbuphine, buprenorphine, butorphanol and pentazocine increase withdrawal of morphine (Nakhjiri et al., 2015). 

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Patient Group Directions (PGDs)

PGDs are guidelines that govern the procurement and administration of medications to groups of patients who may not be personally acknowledged before appearance for treatment (NHS, 2008). PGDs are deployed under circumstances where drug usage follows a predictable pattern and is less personalized. Typical situations include emergency pain relief and accident and accident management, which makes morphine a suitable for administration through PGD. Furthermore, PGDs are appropriate for managing individual treatment episodes in which supply and management of medication is a must but are not suitable for maintaining long-term medical conditions.  

Medical personnel involved in the administration of medicine through PGDs must adhere to specific guidelines. First, they must have current knowledge concerning clinical conditions managed through PGDs, the medication, and its use for the symptoms stated.  Secondly, they must have undergone the relevant training needed for management of PGD (NHS, 2008). Third, they must be satisfied that the PGD is legal, within the date of expiry, and approved by the National Health Service. Lastly, they must ensure that the stipulated procedure is followed during administration and the instructions contained in the PGD are documented. 

A PGD cannot be used to approve the supply and management of medications without a United Kingdom license. They are only allowed for drugs provided and administered out with the terms of the local license if suitable evidence supporting their administration is contained in the PGD. PGDs are developed by a team comprising doctors, pharmacists, and an associate from a professional body, who will be working under the PGD (Piers et al., 2016). Additionally, they most consult with all stakeholders including consultants whose patients are included in the PGD to ensure that the proposed directions do not endanger the safety of the patients and are in line with professional relationships and obligations. Before it is adopted, they PGD must be submitted to the NHS for approval (NHS, 2008). It will ensure that the supply and administration of the PGD are by NHS’s protocols and formularies. 

PGD’s are reviewed every 24 months otherwise it is considered invalid. It should not be utilized after its date of expiration.  Consideration of the PGD must be undertaken by the original authors or their alternatives, but consultation with stakeholders must also be done. Medical personnel using the PGD are responsible for ensuring that the PGD is current and it updated, reviewed, and submitted for re-approval before its date of expiry (NHS, 2008). In case changes are introduced to the PGD, clinical situation, or the illness to which the PGD applied, or to the composition of the medical staff authorized to administer the PGD or the treatments in the PGD, the new instructions must be submitted for deliberation and authorization. 

A PGD must contain information including the patient group, clinical condition, inclusion and exclusion criteria, caution, and direction that must be taken in case the patient refuses treatment. Medicine supplied to a PGD must contain accurate information such as dosage, route, and form of administration, the frequency of administration, the legal status of the medications, warnings, and contraindications. The other requirement of a PGD is the need for nominated persons such as a registered nurse or manager in charge to approve and maintain a current record of individuals permitted to procure and administer medications under the PGD in their section of jurisdiction (NHS, 2008).  

Morphine can be supplied as a PGD because its usage follows a predictable pattern.  Morphine is used in the management of moderate to severe pain. Therefore, patients suffering from moderate to severe pain in a PGD. However, conditions that forms the exclusion criteria to be included in the PGD include having renal impairment, heart conditions or patients taking amphetamines.   

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Legal and Ethical Frameworks

The use of morphine is guided by legal and moral frameworks. Legal guidelines dictate how the drug is ordered into the ward, stored and disposed of, and its use in a PGD. Morphine is controlled drug; therefore, it cannot be bought without a prescription.  Morphine must be requisitioned through the ward Controlled Drugs order book that must be signed by the Registered Nurse who is also a signatory for Controlled Drugs for the ward section (NHS, 2008).  The requisition should indicate the name, type, and strength of morphine, and the amount needed. Additionally, morphine must be requested according to the agreed timetable so that adequate quantities are available to avoid ordering before the agreed schedule.

Concerning the transfer of morphine from one ward to another when the pharmacy is closed, the transfer must be documented in the medicine transfer record book (Williams, 2007). Furthermore, the transfer must be registered in the Controlled Drugs Register of the two wards. The assigned nurse in charge of the ward containing morphine must authorize the removal of the drug from the controlled drugs cupboard. Storage of morphine is not governed by the misuse of medication regulations of 1973, but following these laws is considered good practice.

The ethical framework that regulates the use of morphine in chronic pain management is that of double effect. This framework is used to justify the administration of medication to manage chronic pain even the medication may have unintended, but foreseeable consequences. The adverse effects of opioid drugs such as morphine include respiratory suppression that may hasten death.  For example, a physician may seek to alleviate the pain of a cancer patient, but understand that administration of the drug may hasten the patient’s death (Akbari & Mirzaei, 2013). The only recourse will be to reduce the dosage, but this may not reduce the pain, which is the intended purpose of the drug. According to the Principle of Double Effect, an action that has both negative and positive consequences us deemed safe if the good effect is intentional and if the bad effect is not realized through an adverse effect, if the action is morally right, and the outcome outweighs the bad outcome. For cancer patients in the later stages of the disease, the use of opioid medication is necessary to alleviate pain. However, respiratory suppression is a side effect that can lead to death hence raising ethical questions regarding the use of morphine to reduce patient in such circumstances. Fears over respiratory suppression may result in undertreatment of a patient who has cancer (Glue et al., 2016).  Most physicians will administer high doses that may lead to respiratory suppression and early death. The conflict between relieving pain and providing comfort and the dangers of the side effects of morphine is an ethical question that can be resolved using the principle of double effect.

Self-administration of Medication

Self-administration of medicines is a situation where the patients administer the medication alone. Under appropriate checks and control, patients can have control of their drugs and apply them as necessary (Tapocik et al., 2013).  Self-administration is suitable for the use of patient own medicine programs, and it promotes the empowerment of patients. However, it is important to implement self-administration after the patient has been assessed and a formal record of the evaluation and agreement made. Nurses, pharmacy staff, and doctors must perform local procedures before self-administration programs are introduced.

However, it is important for the medical staff to evaluate the ability of patients to self-administer because of this ability mat change during hospital admission. Safe and secure storage of medications is also advised when implementing self-administration of medicines (Carrillo-Calzadilla et al., 2016). Medical personnel must ensure that patients satisfy the criteria for self-administration of drugs.  The first criteria are that the patient must be taking medications and willing to take part in the program. Secondly, the patient most not appear to be forgetful or confused. Third, the patient must be able to read medical labels correctly. The other considerations include the ability of the patient to open medicine containers and the locker, and whether the patient understands the purpose of the medication (Shadangi et al., 2012). 

Morphine is a medication that can be self-administered by the patient. Intravenous administration of morphine is possible because technologies have been developed that allow patients suffering from terminal illness and experience severe pain to administer medications alone (Mierzejewski et al., 2003). However, two ethical questions arise concerning self-administration of morphine. First, there is the possibility that self-administration of morphine can make patients vulnerable to over-medication. Secondly, there is the issue of addiction to medications, which is commonly associated with opioid medications. Concerns exist regarding the use of drugs to self-regulate pain, which may result from escalating drug use and addictive behaviors (Lucantonio et al., 2015). Although research studies have been conducted to assess the ability of the patients to develop addictive behaviors towards morphine, the results have been inconclusive. 

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Conclusion

As noted in the paper, Morphine is common painkiller used in pain management pain, and it falls into a group of medications known as narcotic analgesics. However, it is Controlled Drug, which means that specific guidelines must be followed in its ordering, storage, and disposal. Morphine must be ordered according to the current Pharmacy Computer Stock Control guidelines for the ordering of drugs. The nurse in charge mist always keeps morphine locked in a cupboard.  Pharmacokinetics of morphine shows that it is actively metabolized the liver, and it is secreted through the urine. It acts mainly on the central nervous system by suppressing pain receptors. Morphine can be deployed in PGDs since they are deployed in circumstances where drug usage follows predictable patterns and is less personalized such in the treatment of long-term pain in cancer patients. Additionally, morphine can be self-administered by the patient. However, this leads to ethical issues surrounding the possibility of addiction to medications, which is commonly associated with opioid medications (Entler et al., 2016). Another ethical issue concerning the use of morphine is the conflict between suppressing pain in cancer patients and the likelihood of respiratory suppression.

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