Can I take antihistamines or Singulair for allergies after a facelift? I'm 4 weeks out.

There is no reason why you shouldn't be able to take those medications after a facelift.  If not sure, it's always best to speak to your surgeon's office rather than online

There should be no issues taking these medications this far after your facelift surgery. In fact, we often have our patients take Benadryl after facelift with laser of they have any itching.That being said, it is always wise to ask the surgeon who performed your surgery first. 

In most cases, one can resume most medications a few days following surgery. By four weeks, healing is well on its way to being established and strong. Antihistamines should not play a significant role in the time it takes to heal if initiated at this point.