Morphine Pharmacology


About Morphine
Mu-opioid agonist,Natural opium alkaloid, A highly potent Narcotic Analgesic.
Mechanism of Action of Morphine
This Opioid analgesic act on the CNS. Its analgesic action is due to the action on Opioid receptors. There are different types of Opioid receptors in the body; they are mu receptors, delta receptors, and kappa receptors etc. Its analgesia, euphoria and dependence are due to its action on mu-1 receptors. It reduces the pain threshold, there by reducing the perception of pain. This action is assisted by the feeling of well being. Respiratory depression and inhibition of intestinal movements is due to its action on mu-2 receptors. Its action on kappa receptors cause spinal analgesia.It directly acts on the cough centre and suppress cough. Morphine also acts on the hypothalamus and pituitary-adrenal cortex and affects several releases of hormones.
Pharmacokinets of Morphine
Absorption-It is slowly absorbed through orally. During sub cutaneous and intravenous administration it is absorbed very rapidly.
Distribution-It is widely distributed throughout body. 50% of it`s seen as bound and rest is seen unbound with plasma protein. It crosses the placental barrier.
Metabolism-It is metabolized in liver by glucoronide conjugation. Morphine 6- glucoronide is one of the active metabolite. During oral administration there is first metabolism.
Excretion- Excreted via urine and through bile.
Onset of Action for Morphine
Intra venous -5min
Intra muscular - 10-30min
Subcutaneous- 10-30min
Epidural and Intrathecal-15-60min.
Duration of Action for Morphine
In the case of oral administration - 4 to 12 hrs
In injection forms - 4 to 5 hrs
In the case of epidural and intra thecal administration - 24 hrs
Half Life of Morphine
In the case of adults plasma half life is 2 hrs. It is longer as glucoronide conjugate.
Side Effects of Morphine
1. Nausea
2. Vomiting
3. Dry mouth
4. Constipation
5. Anorexia
6. Sedation
7. Euphoria
8. Nightmares
9. In large dose there is seizures may be seen.
10. Hypotension
11. Cardiac arrest
12. Arrythmia
13. Thrombocytopenia
14. Apnea
15. Respiratory arrest
16. Pruritis
17. Edema
18. In the case of long term use there is physical dependence
Contra-indications of Morphine
1.In geriatric and debilitated patient it is cautiously used because it cause urinary retention in sometime
2.In patients with head injury, increased intra cranial pressure, seizures, pulmonary disease, hepatic or renal failure, Addison`s disease etc
3.It is also contraindicated in patients with hypersensitive reaction with other Opioid drugs
4.It is contraindicated in pregnancy and lactation
Special Precautions while taking Morphine
1.It is cautiously used in patients with respiratory insufficiency
2. Liver
3. Kidney failure
4. Hypothyroidism
5. Unstable personalities

Pregnancy Related Information
Use with caution
Old Age Related Information
Use with caution
Breast Feeding Related Information
Use with caution
Children Related Information
Use with caution
Indications for Morphine
1. Pain due to -cancer, Acute myocardial infarction, Angina, labour etc
2. Preoperative sedation
3. Post operative analgesia
4. Adjunctive treatment of acute pulmonary Oedema.
5. Adjuncts to anesthesia
Interactions for Morphine
Typical Dosage for Morphine
Adults -
5 to 20 mg aqueous solution given for every 4 hrs, which relieve moderate to severe pain .
For the suppression of cough 5mg oral solution given for every 4 hrs or controlled release tablet 15 to 30mg for every 12 hrs
Intra venous-
For relieving severe pain: initially 15mg as a loading dose which is followed by 0.8 to 10mg/hr continuously
For sedation and anesthesia: 8-10mg
For relieving acute pulmonary Oedema: 5-10mg at rate of 2mg/min.
Intramuscular and Sub cutaneous - 10 mg every 4 hrs.
Epidural- initially 5mg injection and then 1-2 mg if necessary.
Intra thecal - 0.2-1mg injection on a single occasion
For children -
0.05 to 0.2 mg /kg for severe pain.
For sedation 8-10mg.
For post operative analgesia 0.01-0.04mg/kg/hr by continuous I.V. infusion
Intramuscular and Sub cutaneous -
6 to 12 yrs 5-10mg
1 to 5 yrs 2.5-5mg.
1 to 12 months 200 mcg/ kg.

Schedule of Morphine
Storage Requirements for Morphine
Stored in a tightly closed, light resistant container at room temperature.
Effects of Missed Dosage of Morphine
Take the missed dose as soon as noticed and if it is the time for next dose then skip the missed dose. Continue the regular schedule. Do not double the dose.
Effects of Overdose of Morphine
Provide supportive measures and symptomatic treatment initially. Establish respiratory exchange .Inducing gastric lavage or emesis. If needed administer morphine antagonist (naloxone).Continue the monitoring of laboratory parameters, vital signs and neurological status closely.

Home Delivery for Morphine in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including morphine.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for morphine and other medicines and health products. Home delivery services for morphine may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take morphine only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for morphine before they complete the sale. You can get this information while placing the order for morphine with the pharmacy.

Morphine is a generic medicine name and there are several brands available for it. Some of the brands for morphine might be better known than morphine itself. If the pharmacy that's willing to deliver medicines to your home doesn't have morphine in stock, you can ask for one of the branded alternatives for morphine.