Interacting drugs - summary

Proton Pump Inhibitors +

Clarithromycin     +   Proton pump inhibitors- Esomeprazole/ Omeprazole/ Rabeprazole or
Proton pump inhibitors- Esomoprazole/ Omeprazole  +Clarithromycin   

  serum conc. of Clarithromycin  and proton pump inhibitor  increased
  Based on available data no special action is required         
  

Sucralfate +   Proton pump inhibitors - Lansoprazole 
coadmin delayed  absorption and bioavailability of the proton pump inhibitor. Take at least 30 minutes prior to sucralfate                      

Proton pump inhibitors - + Azole antifungals -  e.g. itraconazole,/  ketoconazole
bioavailability of certain antifungals decreased because of possible reduction in tablet dissolution in presence of high gastric pH.  Avoid concomittant administration  
           

Proton pump inhibitors- esomeprazole / omeprazole  + Benzodiazepines  
 oxidative metabolism of certain benzodiazepines (e.g diazepam,  triazolam ) decreased, reducing clerance, prolonging  clearance, prolonging   half life and increasing  serum levels of benzodiazepine.    Reduce benzodiazepine dosage or increase dosing interval 

Proton pump inhibitors - omeprazole +  Cilostazol
 concurrent use increase cilostazol plasma conc. increasing the  therapeutic and adverse effects.  Consider dosage adjustment of  cilostazol                 

Proton pump inhibitors  +  Digoxin    
 coadmin.  increase  serum digoxin levels. Magnitude may not be clinically  important in most patients
                                                  
Proton pump inhibitors - Omeprazole  + Hydantoins/  phenytoin
 serum hydantoin levels increased, because omeprazole inhibiting the   oxidative hepatic oxidation. Consider monitoring serum hydantoin levels    and adjust dosage as needed                            

Proton pump inhibitors  + Salicylates
 enteric-coated salicylates dissolve rapidly, increasing gastric  side effects

Proton pump inhibitors - Omeprazole   + sulfonylureas 
 concurrent use increase serum sulfonylurea conc. increasing  the hypoglycemic effects. based on data no special action is  needed.

Proton pump inhibitors  +  Warfarin 
 reports of changes in prothrombin measures received among  patients on concomittant warfarin and proton pump inhibitor. Monitor  international normalized ratio (INR ) and prothrombin time 

U.S FDA  APPROVED DRUGS FROM 01-01-08 TO 31-12-08

U.S FDA APPROVED DRUGS DURING 2007

Reflux osesophagitis

Proton pump inhibitors include-

    Esomeprazole, Lansoprazole, Omeprazole, Pantoprazole, Rabeprazole
    Refer - Omeprazole

INFORMATION UPDATE-

PPIs -  RISK OF ARRHYTHMIAS, CONVULSION-

Studies have shown that  two out every three people consuming Proton Pump Inhibitor (PPIs) such as omeprazole, pantroprazole, lansoprazole, esomeprazole and rabeprazole do not suffer from disorders for which the drugs are indicated. Besides,

- These agents are being used for unnecessary prolonged periods. Using them for more
  than one month can lead to rebound hypersecretion with the result that patients start taking
  again creating a long term depedence 

- PPIs increase the risk of fractures of the hip, spine, and wrist, serious infections such as
  pneumonia and life threatening C. difficile diarhoea

- Low serum , magnesium levels, (hypomagnesiumia) if taken for a prolonged period of time.  Low serum magnesium levels can result in serious adverse events including  muscle spasms  (tetany), irreguar heart beats ( arhythmias) and convulsions (seizures )

 Treatment of hypomagnesiumia generally requires magnesium supplements. However, in
 approximately one quarter of the cases, magnesium supplemention alone does improve
 low serum magnesium levels and PPIs needs to be discontinued

- PPIs  may also reduce the efficacy  of other drugs used to treat heart attacks and cancer

-   

Adverse Reactions

Omeprazole-

CNS-   Headache   6%, Dizziness 1.%      Asthenia            1.%              
 
GI-   Diarrhea  3%, Abdominal pain  2.% , Nausea  2%, Vomiting 1.%, 

Constipation 1%               

                                                                           
Miscellaneous - Upper-respiratory infection   2% ,   Rash  2%    Cough  1% 

  Back pain  1%                
                         
                          
                       

Hypersens,pregnancy,lactation,children.

Warnings-

Gastritis - atrophic gastritis has been noted occassionally in gastric corpus biopsies
of patients  treated from patients long term with esomeprazole and omeprazole  

Hepatic effects- mild transcient transaminase elevations have been observed in
 IV panoprazole clinical studies. The clinical significance unknown.

Vitamin B12 defeciency - generally daily treatment with any acid suppressing
medications over long period of time ( over 3 years ) may lead to malabsoption
of cyanocobalamine ( vitamin B12 ) caused by hypo  or achlorhydria.
Consider this possibilty if clinical symptoms consistent with cycanocobalamine
defeciency is observed.

Hypersensitivity reactions - anaphylaxis has been reported with the use of
IV  pantoprazole . This may require emergency treatment

Special Precautions:

Exclude malignancy before and after treatment. Prolonged use.

Maintenance therapy- Omeprazole shoiuld not be used as maintenance therapy
for treatment of patients  with duodenal ulcer disease.

Duration of therapy- (GERD) the efficacy of omeprazole used for > 8 weeks has
not been established. In rare patients not responding to 8 weeks of treatment, an additional 4 weeks  of treatment may help.
 If there is recurrence  of severe or symptomatic GERD poorly responsive to customary medical treatment, an additional  4 to 8 weeks of omeprazole may be considered.

Atropic gastritis- has been noted occassionally in gastric corpus biopsies from
patients treated  long-term with omeprazole.

Carcinogenesis- An usual primary malignant tumor in the stomach was seen in one rat.

Elderly- Bioavilability may be increased

Pregnancy- There are no adequate and well controlled studies in pregnant women.
Use during pregnancy only if the potential beneft justifies the risk of to the fetus

Lactation- Decide whether to discontinue the drug or discontunue nursing depending upon the  importance of the drug to the mother.

Children- Safety and efficacy in children have not been established.

Patent Position: Expires  2 April 1999

Duodenal ulcer, Gastroesophagal reflux disease,Zollinnger-Ellison Syndrome

Dosage:
Take before eating - 20mg 4 times daily for 4 to 8 weeks.

Overdosage-  Symptoms                                                             

Confusion, drowsiness, blurred vision, tachycardia, nausea,  diaphoresis, flushing, headache ,  dry mouth. Symptoms were transcient and no serious clinical outcome has been reported.                                                                                               

Treatment
                        
1. No specific antidote known
2. Omeprazole is extensively protein bound and therfore not dialyzable
3. Treatment should be symptomatic and supportive

Missed dose-

1. If you miss a dose of this medicine, take it as soon as possible.
2. However, if it is almost time for next dose, skip the missed dose and go back to your
  regular dosing schedule.
3. Do not double doses. 

For Availability/supplies 

GASTRO OSEPHAGEAL REFLUX DISEASE (GORD)

Evidence Based Medicine (MIMS- March 2003)

Beneficial

1. Proton Pump Inhibitors such as omeprazole, Lansoprazole, pantoprazole

2. H-2 Antagonists such as cimetidine, ranitidine, famotidine, (less than proton pump inhibitors)

3. Fundoplication

Likely to be beneficial

1. Medical and surgical tretment of GORD in selected patients with extraoesophageal manifestations.

Unknown effectiveness

1. Medical and surgical treatment of GORD in patients with Barrets oesophagus

2. Surgical treatment for non erosive oesophagitis

Key Points

1. One systemic review of randomised clinical trials has found proton inhibitors to be more effective than H-2 antagonists in both erosive and non-erosive oesophagitis. One trial has found no significant differences in the effectiveness of different proton pump inhibitors

2. Surgical treatment has not been adequately evaluated in controlled clinical trials. Medical and surgical treatments have not been adequately compared

3. It is not clear whether patients with Barretts oesophagitis benefit from medical or surgical treatment of their gastro oesophageal reflux

4. There is limited, conflicting evidence on the basis on the benefits of treating gastro oesophageal reflux in patients with extra oesophageal manifestations (such as asthma)

Refer - Omeprazole 

1.Swallow the capsule form of Omeprazole whole.Do not crush,break,chew or open the capsule.

2.Take this for the full time of treatment, even if you begin to feel better.

3.If you miss a dose of this medicine take it as soon as possible. However,if it is almost time for the next dose,skip the missed dose and go back to your regular dosing schedule. Do not double dose.

4.Allergies- tell your doctor if you have ever had any unusual or allergic reaction to omeprazole Also tell your doctor if you are allergic to any other substances, such as foods, presevatives or dyes.

5.Pregnancy - studies in animals have shown that omeprazole may cause harm to fetus.

6.Breast feeding- omeprazole may paas into breast milk. make sure that you have discussed the risks and benefits of the medicine with your doctor.

7. Children - no specific information comparing use of nitrates in children with use in other age groups

8.Elderly- no specific information comparing use of omeprazole in the elderly with use in other age groups

9. Other medicines - Antocoagulants or Diazepam or Phenytoin - use with omeprazole may cause high blood levels of these medicines which may increase the chance of side effects.

10. Other medical problems - Tell your doctor if you have any other medical problems especially - Liver disease or history of liver disease- the condition may cause ompeprazole to build up in the body.

11. Missed dose - If you miss a dose of this medicine, take it as soon as possible. however, if it is almost time for the next dose, skip the missed dose. Do not double doses.

12. Storage - Keep out of reach of children. Store away from heat or direct sunlight. Do not store the capsule in bathroom, near the kitchen sink, or in other damp places.

13. Outdated medicines - Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of reach of children.

Absorption may be delayed.

Pregnancy:

Omeprazole Catogery

C Esnoprazole , Lanzoprazole - Category B

No adequate or well controlled studies in pregnant women. Use during pregnancy only if the potential benefit justifies the risk to the fetus.

Lactation:

Not known whether omoprezole is excreted in breast milk. Decide whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.