Therapeutic Drug Monitoring
This is essential for patients being treated with aminoglycosides (gentamicin, amikacin, streptomycin),
vancomycin and flucytosine (5-FC) : adequate peak blood levels are necessary for a therapeutic effect,
trough levels indicate whether there is sufficient renal clearance to minimise toxicity. Antimicrobial Therpaeutic Drug Monitoring may be warranted with other drugs in special clinical situations.
These include checks on compliance (rifampicin for tuberculosis), absorption (itraconazole),
accumulation in patients with renal impairment (high dose co-trimoxazole for Pneumocystis;
penicillin, teicoplanin and ciprofloxacin in severe renal failure), and adequacy of dosage
in deep-seated infections such as endocarditis, osteomyelitis, non-inflammatory or chronic meningitis,
and syphilis (especially if these are treated with penicillin, amoxycillin, or teicoplanin - drug levels
may be measured directly, or 'back-titration' against the patient's own infecting organism may be used
to determine the bacteriostatic/bactericidal levels achieved in the blood).
PLEASE NOTE: VANCOMYCIN LEVELS - From 5th October 2015, Vancomycin results are approximately 11% lower than previously reported

Investigation:                          Antibiotic Assay See Hospital Formulary

Inform lab before sending:     See Table:


Drug
Note:
Turnround Time:
Sample Info:
Additional Info:
Amikacin
Advance warning not required unless urgent
<24 Hours
Clot Activator (red top).
Volume 5-10mls
(For neonates 0.5-2ml in a small heparin tube will suffice)
Performed by Biochemistry
Teicoplanin
Advance warning not required unless urgent
<24 Hours
Clot Activator (red or gold top)
the Gold Top sample must be received within 12hr of sample collection 
 Volume 5-10mls
(For neonates 0.5-2ml)
Pre dose sample is required for routine monitoring. Add-on requests for Teicoplanin is not accepted 12-hours post sample collection. Performed in Biochemistry
Gentamicin
Advance warning not required unless urgent
< 4 Hours
Clot Activator (red or gold top)
Performed in Biochemistry
Tobramycin
Advance warning not required unless urgent
< 24 Hours
Clot Activator (red top).
Volume 5-10mls
(For neonates 0.5-2ml in a small heparin tube will suffice)
Performed in Biochemistry
Vancomycin
Advance warning not required unless urgent
< 4 Hours
Clot Activator (red or gold top)
 the Gold Top sample must be received within 8hr of sample collection
Performed in Biochemistry
Benzylpenicillin
24 hour advance warning essential
Mon-Fri:48hrs - Reference Lab Referral
 
 
Ciprofloxacin
24 hour advance warning essential
Mon-Fri:48hrs - Reference Lab Referral
 
 
Cotrimoxazole
24 hour advance warning essential
Mon-Fri:48hrs - Reference Lab Referral
 
 
Cycloserine
24 hour advance warning essential
Mon-Fri:4 days - Reference Lab Referral
 
 
Flucytosine
24 hour advance warning essential
Mon-Fri:48hrs - Reference Lab Referral
 
 
Rifampicin
24 hour advance warning essential
Mon-Fri:48hrs - Reference Lab Referral
 
 
Moxifloxacin
24 hour advance warning essential
Mon-Fri:48hrs - Reference Lab Referral
 
 
Streptomycin
24 hour advance warning essential
Mon-Fri:48hrs - Reference Lab Referral
 
 
Others
24 hour advance warning essential
Please discuss with the laboratory
 
 



Specimen type:                       Whole Blood

Volume:                                   5-10 ml (For neonates 0.5 – 2ml of blood in a small heparin tube will suffice)

Ideal time to take specimen:   Pre-dose levels up-to 30 mins before next dose is administered
                                                Post-dose levels 1 hour after the dose has been administered 





Labelling:
                 Specimens must have:

• Unit number/A+E number or date of birth
• Full name (forename and surname)
• Specimen type ( e.g. Pre-dose, Post –dose or Random)
• Date & time of collection

                 Request forms must have: