Morphine ER

Important Dosage and Administration Instructions

Morphine sulfate extended-release tablets should be prescribed only by healthcare professionals who are knowledgeable in the use of potent opioids for the management of chronic pain.

Morphine sulfate extended-release tablets100 mg and 200 mg capsules, a single dose greater than 60 mg, or a total daily dose greater than 120 mg, are only for use in patients in whom tolerance to an opioid of comparable potency has been established.

Patients considered opioid-tolerant are those taking, for one week or longer, at least 60 mg morphine per day, 25 mcg transdermal fentanyl per hour, 30 mg oral oxycodone per day, 8 mg oral hydromorphone daily, 25 mg oral oxymorphone per day, 60 mg oral hydrocodone per day, or an equianalgesic dose of another opioid.

• Use the lowest effective dosage for the shortest duration consistent with individual patient treatment goals [see Warnings and Precautions (5)].
• Initiate the dosing regimen for each patient individually, taking into account the patient's severity of pain, prior analgesic treatment experience, and risk factors for addiction, abuse, and misuse [see Warnings and Precautions (5.1)].
• Monitor patients closely for respiratory depression, especially within the first 24-72 hours of initiating therapy and following dosage increases with morphine sulfate extended-release tablets and adjust the dosage accordingly [see Warnings and Precautions (5.2)].

Instruct patients to swallow morphine sulfate extended-release tablets whole [see Patient Counseling Information (17)]. Crushing, chewing, or dissolving morphine sulfate extended-release tablets will result in uncontrolled delivery of morphine and can lead to overdose or death [see Warnings and Precautions (5.1)].

Morphine sulfate extended-release tablets is administered orally once every 8 or 12 hours.

Initial Dosage

Use of morphine sulfate extended-release tablets as the First Opioid Analgesic (opioid-naïve patients)

Initiate treatment with morphine sulfate extended-release tablets with 15 mg tablets orally every 8 or 12 hours.

Use of morphine sulfate extended-release tablets in Patients who are not Opioid Tolerant (opioid non-tolerant patients)

The starting dose for patients who are not opioid tolerant is morphine sulfate extended-release tablets15 mg orally every 12 hours.

Use of higher starting doses in patients who are not opioid tolerant may cause fatal respiratory depression.

Conversion from Other Oral Morphine to Morphine sulfate extended-release tablets

Patients receiving other oral morphine formulations may be converted to morphine sulfate extended-release tablets by administering one-half of the patient's 24-hour requirement as morphine sulfate extended-release tablets on an every-12-hour schedule or by administering one-third of the patient's daily requirement as morphine sulfate extended-release tablets on an every-8-hour schedule.

Conversion from Other Opioids to Morphine sulfate extended-release tablets

Discontinue all other around-the-clock opioid drugs when morphine sulfate extended-release tablets therapy is initiated.

There are no established conversion ratios for conversion from other opioids to morphine sulfate extended-release tablets defined by clinical trials.  Initiate dosing using morphine sulfate extended-release tablets 15 mg orally every 8 to 12 hours.

It is safer to underestimate a patient's 24-hour oral morphine dosage and provide rescue medication (e.g., immediate-release opioid) than to overestimate the 24-hour oral morphine dosage and manage an adverse reaction due to an overdose. While useful tables of opioid equivalents are readily available, there is inter-patient variability in the potency of opioid drugs and opioid formulations. Close observation and frequent titration are warranted until pain management is stable on the new opioid. Monitor patients for signs and symptoms of opioid withdrawal and for signs of oversedation/toxicity after converting patients to morphine sulfate extended-release tablets.

Conversion from Parenteral Morphine or Other Opioids (Parenteral or Oral) to Morphine sulfate extended-release tablets

When converting from parenteral morphine or other non-morphine opioids (parenteral or oral) to Morphine sulfate extended-release tablets, consider the following general points:

Parenteral to oral morphine ratio: Between 2 to 6 mg of oral morphine may be required to provide analgesia equivalent to 1 mg of parenteral morphine. Typically, a dose of morphine that is approximately three times the previous daily parenteral morphine requirement is sufficient.

Other parenteral or oral non-morphine opioids to oral morphine Ratios: Specific recommendations are not available because of a lack of systematic evidence for these types of analgesic substitutions. Published relative potency data are available, but such ratios are approximations. In general, begin with half of the estimated daily morphine requirement as the initial dose, managing inadequate analgesia by supplementation with immediate-release morphine.

Conversion from Methadone to Morphine sulfate extended-release tablets

Close monitoring is of particular importance when converting methadone to other opioid agonists. The ratio between methadone and other opioid agonists may vary widely as a function of previous dose exposure. Methadone has a long half-life and can accumulate in the plasma.

Titration and Maintenance of Therapy

Individually titrate morphine sulfate extended-release tablets to a dose that provides adequate analgesia and minimizes adverse reactions. Continually reevaluate patients receiving morphine sulfate extended-release tablets to assess the maintenance of pain control and the relative incidence of adverse reactions, as well as monitoring for the development of addiction, abuse, or misuse [see Warnings and Precautions (5.1)]. Frequent communication is important among the prescriber, other members of the healthcare team, the patient, and the caregiver/family during periods of changing analgesic requirements, including initial titration. During chronic therapy periodically reassess the continued need for the use of opioid analgesics.

Patients who experience breakthrough pain may require a dosage adjustment of morphine sulfate extended-release tablets, or may need rescue medication with an appropriate dose of an immediate-release analgesic. If the level of pain increases after dose stabilization, attempt to identify the source of increased pain before increasing the morphine sulfate extended-release tablets dosage. Because steady-state plasma concentrations are approximated in 1 day, morphine sulfate extended-release tablets dosage adjustments may be done every 1 to 2 days.

If unacceptable opioid-related adverse reactions are observed, consider reducing the dosage. Adjust the dosage to obtain an appropriate balance between management of pain and opioid-related adverse reactions.

Dosage Modifications with Concomitant Use of Central Nervous System Depressants

If the patient is currently taking a central nervous system (CNS) depressant and the decision is made to begin morphine sulfate extended-release tablets, start with the lowest possible dose, 15 mg every 12 hours, monitor patients for signs of respiratory depression, sedation, and hypotension, and consider using a lower dosage of the concomitant CNS depressant [see Warnings and Precautions (5.4), Drug Interactions (7)].

Discontinuation of Morphine Sulfate Extended-Release Tablets

When a patient no longer requires therapy with morphine sulfate extended-release tablets, taper the dose gradually, by 25% to 50% every 2 to 4 days, while monitoring carefully for signs and symptoms of withdrawal. If the patient develops these signs or symptoms, raise the dose to the previous level and taper more slowly, either by increasing the interval between decreases, decreasing the amount of change in dose, or both. Do not abruptly discontinue morphine sulfate extended-release tablets [see Warnings and Precautions (5.12), Drug Abuse and Dependence (9.3)].

Morphine sulfate extended-release tablets are contraindicated in patients with:

• Significant respiratory depression [see Warnings and Precautions (5.2)]
• Acute or severe bronchial asthma in an unmonitored setting or in the absence of resuscitative equipment [see Warnings and Precautions (5.5)]
• Concurrent use of monoamine oxidase inhibitors (MAOIs) or use of MAOIs within the last 14 days [see Warnings and Precautions (5.6), Drug Interactions (7)] .
• Known or suspected gastrointestinal obstruction, including paralytic ileus [see Warnings and Precautions (5.10)]
• Hypersensitivity (e.g., anaphylaxis) to morphine [see Adverse Reactions (6.2)]

Clinical Presentation

Acute overdosage with morphine sulfate extended-release tablets can be manifested by respiratory depression, somnolence progressing to stupor or coma, skeletal muscle flaccidity, cold and clammy skin, constricted pupils, and, in some cases, pulmonary edema, bradycardia, hypotension, partial or complete airway obstruction, atypical snoring, and death. Marked mydriasis rather than miosis may be seen with hypoxia in overdose situations.

Treatment of Overdose

In case of overdose, priorities are the re-establishment of a patent and protected airway and institution of assisted or controlled ventilation, if needed. Employ other supportive measures (including oxygen and vasopressors) in the management of circulatory shock and pulmonary edema as indicated. Cardiac arrest or arrhythmias will require advanced life support techniques.

The opioid antagonists, naloxone or nalmefene, are specific antidotes to respiratory depression resulting from opioid overdose. For clinically significant respiratory or circulatory depression secondary to morphine overdose, administer and opioid antagonist. Opioid antagonists should not be administered in the absence of clinically significant respiratory or circulatory depression secondary to morphine overdose.

Because the duration of reversal would be expected to be less than the duration of action of morphine in morphine sulfate extended-release tablets, carefully monitor the patient until spontaneous respiration is reliably reestablished. Morphine sulfate extended-release tablets will continue to release morphine and add to the morphine load for 24 to 48 hours or longer following ingestion, necessitating prolonged monitoring. If the response to opioid antagonists is suboptimal or only brief in nature, administer additional antagonist as directed by the product's prescribing information.

In an individual physically dependent on opioids, administration of the usual dose of the recommended usual dosage of the antagonist will precipitate an acute withdrawal syndrome. The severity of the withdrawal symptoms experienced will depend on the degree of physical dependence and the dose of the antagonist administered. If a decision is made to treat serious respiratory depression in the physically dependent patient, administration of the antagonist should be initiated with care and by titration with smaller than usual doses of the antagonist.

Mechanism of Action

Morphine is a full opioid agonist and is relatively selective for the mu-opioid receptor, although it can bind to other opioid receptors at higher doses. The principal therapeutic action of morphine is analgesia. Like all full opioid agonists, there is no ceiling effect for analgesia with morphine. Clinically, dosage is titrated to provide adequate analgesia and may be limited by adverse reactions, including respiratory and CNS depression.

The precise mechanism of the analgesic action is unknown. However, specific CNS opioid receptors for endogenous compounds with opioid-like activity have been identified throughout the brain and spinal cord and are thought to play a role in the analgesic effects of this drug.

Pharmacodynamics

CNS Depressant/Alcohol Interaction

Additive pharmacodynamic effects may be expected when morphine sulfate extended-release tablets is used in conjunction with alcohol, other opioids, or illicit drugs that cause central nervous system depression.

Effects on the Central Nervous System

Morphine produces respiratory depression by direct action on brainstem respiratory centers. The respiratory depression involves a reduction in the responsiveness of the brainstem respiratory centers to both increases in carbon dioxide tension and electrical stimulation.

Morphine causes miosis, even in total darkness. Pinpoint pupils are a sign of narcotic overdose but are not pathognomonic (e.g., pontine lesions of hemorrhagic or ischemic origins may produce similar findings). Marked mydriasis rather than miosis may be seen with hypoxia in overdose situations.

Effects on the Gastrointestinal Tract and Other Smooth Muscle

Morphine causes a reduction in motility associated with an increase in smooth muscle tone in the antrum of the stomach and in the duodenum. Digestion of food in the small intestine is delayed and propulsive contractions are decreased. Propulsive peristaltic waves in the colon are decreased, while tone may be increased to the point of spasm, resulting in constipation. Other opioid-induced effects may include reduction in biliary and pancreatic secretions, spasm of the sphincter of Oddi, and transient elevations in serum amylase.

Effects on the Cardiovascular System

Morphine produces peripheral vasodilation which may result in orthostatic hypotension or syncope. Manifestations of histamine release and/or peripheral vasodilation may include pruritus, flushing, red eyes, sweating, and/or orthostatic hypotension.

Effects on the Endocrine System

Opioids inhibit the secretion of adrenocorticotropic hormone (ACTH), cortisol, and luteinizing hormone (LH) in humans [see Adverse Reaction (6.2)]. They also stimulate prolactin, growth hormone (GH) secretion, and pancreatic secretion of insulin and glucagon.

Chronic use of opioids may influence the hypothalamic-pituitary-gonadal axis, leading to androgen deficiency that may manifest as low libido, impotence, erectile dysfunction, amenorrhea, or infertility. The causal role of opioids in the clinical syndrome of hypogonadism is unknown because the various medical, physical, lifestyle, and psychological stressors that may influence gonadal hormone levels have not been adequately controlled for in studies conducted to date [see Adverse Reactions (6.2)].

Effects on the Immune System

Opioids have been shown to have a variety of effects on components of the immune system in in vitro and animal models. The clinical significance of these findings is unknown. Overall, the effects of opioids appear to be modestly immunosuppressive.

Concentration-Efficacy Relationships

The minimum effective analgesic concentration will vary widely among patients, especially among patients who have been previously treated with potent agonist opioids. The minimum effective analgesic concentration of morphine for any individual patient may increase over time due to an increase in pain, the development of a new pain syndrome, and/or the development of analgesic tolerance [see Dosage and Administration (2.1, 2.2)]

Concentration–Adverse Reaction Relationships

There is a relationship between increasing morphine plasma concentration and increasing frequency of dose-related opioid adverse reactions such as nausea, vomiting, CNS effects, and respiratory depression. In opioid-tolerant patients, the situation may be altered by the development of tolerance to opioid-related adverse reactions [see Dosage and Administration (2.1, 2.2, 2.3)].

Pharmacokinetics

Absorption

Morphine sulfate extended-release tablets is an extended-release tablet containing morphine sulfate. Morphine is released from morphine sulfate extended-release tablets somewhat more slowly than from immediate-release oral preparations.  Following oral administration of a given dose of morphine, the amount ultimately absorbed is essentially the same whether the source is morphine sulfate extended-release tablets or an immediate-release formulation. Because of pre-systemic elimination (i.e., metabolism in the gut wall and liver) only about 40% of the administered dose reaches the central compartment.

The oral bioavailability of morphine is approximately 20 to 40%. When morphine sulfate extended-release tablets is given on a fixed dosing regimen, steady-state is achieved in about a day.

Food Effect

The effect of food upon the systemic bioavailability of morphine sulfate extended-release tablets has not been systematically evaluated for all strengths. One study, conducted with the 30 mg morphine sulfate extended-release tablets, showed no significant differences in Cmax and AUC (0-24h) values, whether the tablet was taken while fasting or with a high-fat breakfast.

Distribution

Once absorbed, morphine is distributed to skeletal muscle, kidneys, liver, intestinal tract, lungs, spleen, and brain. Morphine also crosses placental membranes and has been found in breast milk. The volume of distribution (Vd) for morphine is approximately 3 to 4 liters per kilogram and morphine is 30 to 35% reversibly bound to plasma proteins.

Elimination

Metabolism

The major pathways of morphine metabolism include glucuronidation to produce metabolites including morphine-3-glucuronide, M3G (about 50%) and morphine-6-glucuronide, M6G (about 5 to 15%) and sulfation in the liver to produce morphine-3-etheral sulfate. A small fraction (less than 5%) of morphine is demethylated. M6G has been shown to have analgesic activity but crosses the blood-brain barrier poorly, while M3G has no significant analgesic activity.

Excretion

The elimination of morphine occurs primarily as renal excretion of M3G and its effective half-life after intravenous administration is normally 2 to 4 hours. Approximately 10% of the dose is excreted unchanged in urine. In some studies involving longer periods of plasma sampling, a longer terminal half-life of about 15 hours was reported. A small amount of the glucuronide conjugate is excreted in the bile, and there is some minor enterohepatic recycling.

Specific Populations

Sex

A sex analysis of pharmacokinetic data from healthy subjects taking morphine sulfate extended-release tablets indicated that morphine concentrations were similar in males and females.

Race/Ethnicity

Chinese subjects given intravenous morphine had a higher clearance when compared to Caucasian subjects (1852 +/- 116 ml/min compared to 1495 +/- 80 ml/min).

Hepatic Impairment

Morphine pharmacokinetics are altered in patients with cirrhosis. Clearance was found to decrease with a corresponding increase in half-life. The M3G and M6G to morphine plasma AUC ratios also decreased in these patients, indicating diminished metabolic activity. Adequate studies of the pharmacokinetics of morphine in patients with severe hepatic impairment have not been conducted.

Renal Impairment

Morphine pharmacokinetics are altered in patients with renal failure. The AUC is increased and clearance is decreased and the metabolites, M3G and M6G, may accumulate to much higher plasma levels in patients with renal failure as compared to patients with normal renal function. Adequate studies of the pharmacokinetics of morphine in patients with severe renal impairment have not been conducted.

Morphine sulfate extended-release tablets 15 mg are round, blue-colored, film-coated tablets, debossed "n 15" on one side and plain on the other side. They are supplied as follows:

NDC 43386-540-01 opaque plastic bottles containing 100 tablets

NDC 43386-540-05 opaque plastic bottles containing 500 tablets

Morphine sulfate extended-release tablets 30 mg are round, lavender-colored, film-coated tablets, debossed "n 30" on one side and plain on the other side. They are supplied as follows:

NDC 43386-541-01 opaque plastic bottles containing 100 tablets

NDC 43386-541-05 opaque plastic bottles containing 500 tablets

Morphine sulfate extended-release tablets 60 mg are round, orange-colored, film-coated tablets, debossed "n 60" on one side and plain on the other side.  They are supplied as follows:

NDC 43386-542-01 opaque plastic bottles containing 100 tablets

NDC 43386-542-05 opaque plastic bottles containing 500 tablets

Morphine sulfate extended-release tablets 100 mg are round, gray-colored, film-coated tablets, debossed "N 100" on one side and plain on the other side. They are supplied as follows:

NDC 43386-543-01 opaque plastic bottles containing 100 tablets

NDC 43386-543-05 opaque plastic bottles containing 500 tablets

Morphine sulfate extended-release tablets 200 mg are capsule-shaped, green-colored, film-coated tablets, debossed "n 200" on one side and plain on the other side. They are supplied as follows:

NDC 43386-544-01 opaque plastic bottles containing 100 tablets

NDC 43386-544-05 opaque plastic bottles containing 500 tablets

Store at 25°C (77°F); excursions permitted between 15° -30°C (59° -86°F)  [see USP Controlled Room Temperature.]

Dispense in a tight, light-resistant container.

CAUTION

DEA FORM REQUIRED

Morphine Sulfate Extended-Release Tablets, 15 mg

Container Label

NDC  43386-540-01

Morphine Sulfate Extended-Release Tablets, 30 mg

Container Label

NDC 43386-541-01

Morphine Sulfate Extended-Release Tablets, 60 mg

Container Label

NDC  43386-542-01

Morphine Sulfate Extended-Release Tablets, 100 mg

Container Label

NDC 43386-543-01

Morphine Sulfate Extended-Release Tablets, 200 mg

Container Label

NDC  43386-544-01