เท้าบวม | Leg Edema

• a  local phenomenon .

• The calcium channels  are primarily  arteriolar dilators . 

  • Since the  venules  lack much muscle they  are not much affected by the Amlodipine. 

  • This  facilitates flooding of  venules and leaks into the peri venular interstitial space. 

  • It may be apt to call Amlodipine induced edema  as a form of  local venous edema.

• This results in near permanent  collection of fluid  especially  near  the ankle.

• Systemic fluid retention has no major role. 

• However few patients may  show an  augmented  RASS  response due to sudden arteriolar dilatation. In these patients  addition of ACEI or ARB may help relieve  edema legs .

• The Amlodipine  induced edema is dose and time dependent .(Cumulative)  . It is mostly benign in nature ,  

• The edema can occasionally be generalised  and weight  gain is  possible .

• Other factors that increase the chance of edema is age , women , obesity. ( They have loose interstitial tissues)

• The calcium blocker induced edema is an exclusive feature of dihydrpyridine group.

• For some reason  , Verapamil and Diltiazem do not  share  this side effect  as  they a balanced Arteriolar and venous dilator.

## Can we use diuretics to treat Amlodipine induced edema legs ?

• Hydrochorthiazide  is rarely useful as the primary problem is not in the renal  retention.

## How to  treat Amlodipine induced edema ?

• Unfortunately the popular combination with diuretics do not work . 

• Angiotensin  inhibitors which has some veno dilatation is shown to reduce this edema  . ( COACH study . Olmesartan / Telmisartan combination  is an option ) .

• It defies logic ,  to  add  another anti HT drug for the sole  purpose of reducing  the side effect of the initial  anti HT drug . 

• Ideally if  your patient is not tolerating  Amlodipine due to edema ,  switch to  an another group of  anti HT drugs.