Saturday 19 August, 2006

Contraindications to metformin

Posted in General Practice, Medicine, Michael Tam, Wards at 19:11 by Michael Tam

Original article by: Michael Tam :: Printer friendly

Metformin hydrochloride is the first line oral hypoglycaemic agent in Australia for the treatment of type 2 diabetes mellitus. It is the medication with the best evidence base for preventing macrovascular complications (1).

However, it is not without problems. Lactic acidosis is a life threatening complication. Luckily, it is fairly rare with an estimated number of cases of 0.03 per 1000 patient years (or 1 case per annum in 30,000 patients on metformin) (2) (3). The mortality of lactic acidosis is close to 50%.

Read the rest of this entry »

Advertisements

How to start oral hypoglycaemic therapy

Posted in General Practice, Medicine, Michael Tam, Wards at 14:10 by Michael Tam

Original article by: Michael Tam :: Printer friendly

Type 2 diabetes mellitus is common, and will become more so with the expanding Australian waistline. The large government funded Australian Diabetes, Obesity and Lifestyle Study (AusDiab) revealed that there are almost a million people over the age of 25 years with diabetes (1). Even more startling is that almost 1 in 4 Australians over the age of 25 either have diabetes or impaired glucose metabolism (impaired glucose tolerance or impaired fasting glycaemia) (1).

Oral hypoglycaemic agents are the first line therapy for patients diagnosed with type 2 diabetes mellitus if lifestyle modifications are insufficient. One or more of these agents should be commenced (except for those who present with non-ketotic hyperosmolar coma whereby insulin should be used).

In a nutshell (2):

Asymptomatic hyperglycaemia

  • metformin (monotherapy preferred) or
  • sulfonylurea (monotherapy or with low dose metformin)

Symptomatic hyperglycaemia and/or obesity

  • metformin (monotherapy) or
  • metformin with sulfonylurea

See below for details

Aim for a target of:

HbA1c < 7.0%

and

Fasting blood glucose < 6.5 mmol/L

Read the rest of this entry »

Wednesday 2 August, 2006

How to change antidepressants

Posted in General Practice, Michael Tam, Psychiatry, Wards at 18:34 by Michael Tam

Original article by: Michael Tam :: Printer friendly

Although starting antidepressants is not outside the realm of common experience (1), the changing of antidepressants is shrouded in the aura of mystic voodoo that many consider to be best left to the psychiatrists. The reality, however, is that there isn’t much to it.

For the first line and most common antidepressants used (SSRIs except fluoxetine, mirtazapine, venlafaxine and the tricyclic antidepressants):

Taper the dose of the first antidepressant by 25% per day (with complete cessation in 4-7 days).

Start the second antidepressant 3 days after the cessation of the first.

Read the rest of this entry »