40. The most effective antibiotic for acne

Doctor Jacob here, and today we're talking about the most effective antibiotic for acne. If you haven't had a chance, go back and catch a few of the earlier episodes talking about the overview of antibiotics, the pros and cons, as well as about tetracycline, doxycycline and minocycline. Today's episode is focusing on sulfamethoxazole trimethoprim, also known as Bactrim, Septra or Sulfatrim. Because it's such a mouthful to say, it's often referred to by those other names. It's a combination of two ingredients, sulfamethoxazole and trimethoprim, together in one pill. The tablets are marked as either single strength tablets or double-strength tablets.

The single strength tablet combines 400 mg of sulfamethoxazole with 80 mg trimethoprim. A double-strength tablet has twice that, so 800 and 160. A typical dose for acne would be one double-strength tablet twice a day.

This drug can treat not only the red pus-filled pimples and zits, but also helps with deeper seated cysts of acne. However, like any oral antibiotic, sulfamethoxazole trimethoprim will not treat clogged pores. It will not open blackheads or whiteheads.

Given that this is the most effective oral antibiotic for the treatment of acne, why don't we use it more often? Most patients experience zero side effects at all. It's however the very rare, but very serious complications that can occurs with this drug that limits our use of it. So I do prescribe it, but only on rare occasions.

Let's talk about potential side effects. Occasionally, mild nausea can come on if the medicine is taken on an empty stomach; not too serious. For patients who are allergic to sulfa drugs, patients may develop a allergic type rash with itchy, rash or hives on the body. If that occurs, the drug should be discontinued immediately, and the patient should avoid all other sulfa drugs as well in the future.

These are minor reactions, let's talk about some of the more serious reactions. There is a type of allergic reaction called drug hypersensitivity syndrome, also known as drug rash with eosinophilia and systemic symptoms. It's a severe reaction which usually results in hospitalization and potential damage to internal organs such as the liver. There is facial swelling, fever, and patients feel ill, so they seek medical attention. Additionally there is, of course, a rash. Treatment is prompt withdrawal of the medication, as well as high dose steroids in the hospital. Very rarely, liver damage with this drug can be irreversible.

That's just one of the potential serious side effects that can occur. Let's talk about another serious side effect called Stevens-Johnson syndrome.

Stevens-Johnson is a serious skin rash, a type of allergic reaction in which the top layer of the skin called the epidermis [unintelligible 00:03:23] and detaches from the underlying dermis. It requires immediate discontinuation of the offending drug and typically results in hospitalization. If the rash affects more than 10% of the body, the condition is no longer named Stevens-Johnson syndrome, but rather it is called Stevens-Johnson syndrome toxic epidermal necrolysis overlap. As the condition progresses to affect more of the body, we rename the condition toxic epidermal necrolysis. Death can occur.

And finally, an exceedingly rare allergic reaction to this drug can be something we call aseptic meningitis, which is inflammation of the membranes surrounding the brain. It presents with headache, neck pain and neck stiffness and a decreased sharpness in the mind. Patients usually feel unwell and seek medical attention. Typically patients will require hospitalization and most patients experience a full recovery if the drug is discontinued promptly. Rarely, permanent brain injury can occur.

So as you can see, with any of these three serious, even potentially deadly side effects, we don't take the use of this drug lightly, so it's not without risk. On the bright side, most patients experience none of these, and the side effects are very, very rare.

The good news for patients taking this for the long-term is that sulfamethoxazole trimethoprim is generally not effective at killing anaerobic bacteria, so that means patients generally do not experience the side effects of loose stools, yeast infection and with repeated courses do not have increased risk for inflammatory bowel diseases. This is in direct contrast with doxycycline and minocycline.

Unfortunately for women who are pregnant, conceiving or breastfeeding, sulfamethoxazole trimethoprim is not safe to take in these situations. On a positive note, for patients who cannot swallow pills it does come in a liquid formulation. Patients taking spironolactone or certain blood pressure drugs of the ACE inhibitor family should have their potassium levels checked carefully if taking sulfamethoxazole trimethoprim, as the combination can significantly raise potassium levels, leading to an increased risk of sudden cardiac death. Also, patients taking the drug Methotrexate should certainly not take sulfamethoxazole trimethoprim, as the combination is typically fatal.

That's a lot of heavy news regarding this subject, however it is a very effective drug and it has done wonders for many patients who need this drug and who cannot take, for whatever reason, isotretinoin. However, there is a very small chance something serious can go wrong when taking this drug.

I'm Doctor Jacob, we'll see you next time.