Omeprazole Injection 20 / 40 mg

The inhibitory effect of omeprazole occurs within 1 hour after oral administration. The maximum effect occurs within 2 hours. The duration of inhibition is up to 72 hours. When omeprazole is stopped, baseline stomach acid secretory activity returns after 3 to 5 days. The inhibitory effect of omeprazole on acid secretion will plateau after 4 days of repeated daily dosing.

The most frequent significant side effects occurring in at least 1% of patients include:

• Central nervous system: headache (7%), dizziness (2%)
• Respiratory: upper respiratory infection (2%), cough (1%)
• Gastrointestinal: abdominal pain (5%), diarrhea (4%), nausea (4%), vomiting (3%), flatulence (3%), acid regurgitation (2%), constipation (2%)
• Neuromuscular and skeletal: back pain (1%), weakness (1%)
• Dermatologic: rash (2%)

Other significant concerns related to side effects are:

• Clostridium difficile-associated diarrhea
• Increased risk of pneumonia
• Osteoporosis-related fractures
• Hypomagnesemia