Mr L is admitted to A & E at the local hospital as he has been experiencing convulsion. He has diagnosed with chronic obstructive pulmonary disease 5 years ago for which he has been prescribed tiotropium and theophylline . His initial blood test results show that he has a peak theophylline serum concentration of 30 mg/L . how long will it take for the theophylline serum concentration to reach 7.5 mg/L?( The half-life of theophylline is 8 hours)
Have you done any of these?