Omeprazole Side Effects, Dosage & Interactions

Drug Class and Mechanism:

Omeprazole belongs to the group of drugs known as the proton pump inhibitors (PPI) which obstructs the acid that is created in a person’s stomach. Some other drugs that belong to the same class are-

  • Esomeprazole (Nexium)
  • Omeprazole (Prevacid)
  • Pantoprazole (Protonix)
  • Rabeprazole (Aciphex)


Proton pump inhibitors (PPI) are utilized for the cure of conditions for example ulcer, the Zollinger-Ellison syndrome and gastro esophageal reflux disease (GERD), all of which are rooted by acid in the stomach. Omeprazole, similar to other PPI’s, obstructs the enzymes (that produce acid) in the stomach wall. As a result of blocking the enzymes, the making of the acid is dwindled, and this permits the esophagus and the stomach to heal.  It was in September 1989 that Omeprazole was approved by the FDA.


About Omeprazole:

Omeprazole is a medicine that is used for cure for conditions in the intestines, stomach and esophagus. The most prominent side effects of Omeprazole are headaches, abdominal pains, diarrhea, queasiness, giddiness, trouble in awakening and insomnia/sleep deprivation.

Bigger risks are associated with consuming this drug, such as- Clostridium difficile-linked diarrhea and hip fractures. The majority patients in intensive care units are being prescribed Omeprazole as a prophylaxis meant for ulcers. Nevertheless this usage is linked with the incidence of pneumonia.  Additional Omeprazole side effects might also comprise bone reconstruction interfering and a B12 vitamin decrease.  Additionally, it is well-known that the drug Omeprazole is well thought of as a vital cause of severe tubulointerstitial nephritis (a swelling of the kidney).


The side effects of Omeprazole that people bear testimony mainly to are as follows:

  • Problem of Constipation
  • Problem of Diarrhea
  • Flatulence
  • Headache
  • Queasiness
  • Vomiting
  • Stomach ache
  • Giddiness
  • Feeling of weakness
  • Lightheadedness
  • Paresthesia
  • Itch
  • Skin rases
  • Urticaria
  • Drowsiness
  • Vertigo
  • Common sensation of being sick
  • Dermatitis
  • Insomnia/Difficulty in sleeping
  • Violent behavior /sensation of agitation
  • Hair loss
  • Hazy vision
  • Problems of Skin
  • Dry mouth
  • Depression
  • Hallucination
  • Excessive sweating
  • Impotence
  • Puzzlement
  • Weakness in Muscle
  • Muscle tenderness
  • Changes in taste
  • Photosensitivity
  • Inflammation of extremities
  • Swelling in the mouth
  • Infections of Gastrointestinal
  • Bone marrow and Blood problems
  • Erythema multiforme
  • Jaundice
  • Syndrome of Stevens-Johnson
  • Poisonous epidermal necrolysis
  • Liver problems
  • Joint ache and arthritis
  • Metabolic troubles
  • Hypersensitivity reaction for example anaphylactic shock and angioedema


*We will be breaking down these side effects of Omeprazole in detail.


Prescribed For:

Omeprazole is taken to treat ulcers and acid-induced swelling of the abdomen as well as duodenum; erosive esophagitis, gastroesophageal reflux disease (GERD); Zollinger-Ellison Syndrome; indigestion; prevention of the upper gastrointestinal blood loss in gravely ailing patients. It is also used in blend with other antibiotics meant for eradicating H. pylori virus in the belly.




Drug Interactions:

 Omeprazole is capable of potentially increasing the absorption of diazepam in the blood, in addition to phenytoin (Dilantin) and warfarin (Coumadin), by lessening the removal of these medicines by means of the liver.


The level of absorption of some drugs might be influenced by acidity in the stomach. As a result, omeprazole in addition to supplementary PPI’s lessen the concentration and absorption of ketoconazole (Nizoral) in the blood and augment the concentration and absorption of digoxin (Lanoxin) in the blood. This possibly will add to the digoxin toxicity and lessen the efficiencyof ketoconazole.


Through unidentified means, omeprazole may raise blood intensity of saquinavir plus diminish blood level of atazanavir and nelfinavir, which are drugs used for curing patients who have infections caused due to HIV (human immunodeficiency virus).


Increased level of diazepam, phenytoin, warfarin, cyclosporine, digoxin.

Decrease in the absorption of iron, ampicillin, ketoconazole.



Omeprazole Side Effects:

Medicines and drugs may lead to some side effects, but lots of people have no side effects, or slight side effects. Confirm with the doctor if a few of these COMMON side effects endure or turn out to be bothersome while using Omeprazole:


  • Problem of Diarrhea
  • Gas
  • Headaches
  • Queasiness
  • Stomach ache
  • Nausea


Immediately try to find medical attention in case any of the below mentioned SEVERE Omeprazole side effects crop up while you are taking Omeprazole:

Severe allergic reaction like:

  • Skin complaints
  • Hives
  • Itch
  • Trouble in breathing
  • Tautness of the chest
  • Inflammation of the lips, mouth, tongue and face
  • Odd hoarseness
  • Bone ache
  • Chest ache
  • Dark urination
  • Hasty, slow, or unbalanced heartbeat

Running a fever

  • Chills
  • Aching throat
  • Red, puffy, scalded, or flaking skin
  • Seizure
  • Harsh diarrhea
  • Harsh stomach ache or cramp
  • Inflammation of the ankles, feet and hands
  • Odd bruising or blood loss
  • Odd or abrupt increase in weight
  • Strange tiredness
  • Changes in vision
  • Paleness of the skin and eyes

This isn’t the entire list of Omeprazole side effects which a person might be prone to. If you’ve got any queries about Omeprazole side effects, get in touch with your doctor or pharmacist. Call your healthcare provider for medical counseling regarding side effects of Omeprazole.



Indication List:

  • Duodenal in addition to gastric ulcers
  • Zollinger-Ellison disorder
  • Reflux esophagitis
  • Prevention of anxiety ulcers in addition to acid aspiration disorder
  • NSAID induced ulcer


Mechanism of action:

It suppresses gastric acid secretion by specific inhibition of enzyme H+K+ ATPase present on secretory surface of parietal cells.




Hypersensitivity, lactation


Onset of effect:

Within 2 to 5 hours


Duration of action:

24 hours


Adverse Omeprazole Effects:

  • Diarrhea
  • Rash
  • Constipation
  • Headaches
  • Vomiting/nausea
  • Abdominal pains
  • Cough
  • Feeling dizzy
  • Asthma
  • Bach aches
  • Malaise
  • Joint pains and muscle cramps
  • Altered liver enzyme
  • Leucopenia
  • Interstitial nephritis
  • Thrombocytopenia
  • Flatulence
  • Increased risk of enteric infections due to reduced acid secretion





Special precautions:

Use cautiously in renal and hepatic dysfunction. Rule out gastric growth especially in aged epileptics. Keep away from alcohol consumption since it might worsen the underlying state and decreases the useful effect of the medicine.

Pediatrics: Not Recommended

Pregnancy: Safety Not Established

Lactatio: Safety Not Established

Elderly: No Special Problems


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