Q: My niece wears a patch for her ADHD and it is working well except for one thing. She complains that “it itches” and wants to pick at the edges. Would it help if I covered it up with a bandage so she can’t scratch at it?
One of the most helpful things about using a patch instead of a pill is the steady amount of medicine you get from a patch. Patches can also help deliver medicines that are hard to get into the bloodstream. Using a patch bypasses the stomach and delivers medicine into your blood through your skin. Some patches are applied daily, such as nitroglycerin and methylphenidate (Daytrana®), most are applied every 3 days (Transderm-Scop®, Duragesic®), and a few such as clonidine (Catapres TTS®) are designed to last a week.
There are two types of medicated patches: reservoir and matrix. The reservoir type has a liquid core surrounded by a membrane controlling how fast the drug moves into the skin. Newer patches use a matrix that combines the drug with the adhesive into a single layer. Drugs available as a patch include nicotine, methylphenidate, nitroglycerin, estrogen, and the analgesics lidocaine, ketoprofen and fentanyl.
Patches are usually more expensive than the tablet forms of medicine and prescription insurance doesn’t always cover them. Another challenge is getting the right amount of “stickiness” on the patch. It needs to stick to your skin without taking off a couple of layers when you remove it. Finally, because the patch stays on for hours or days, some people develop irritation at the site of the patch.
The most common problem reported with patches is redness and itching where the patch was applied. There are 2 types of skin reactions caused by wearing a patch: irritant dermatitis and allergic dermatitis. Irritant dermatitis can be annoying but there are strategies that can help that. Allergic dermatitis will not get better and you need to stop using the patch.
Irritant contact dermatitis shows up as a red area limited to the exact shape of the patch, and fades over several days after the patch is removed. If you see sharp boundaries of redness when removing the patch, it is most likely irritation.
An allergic reaction to a patch is different. It works like a reaction to poison ivy: first your body comes in contact with the patch. Then days, months or years later, your body decides that some component in that patch is a threat to you, and your immune system goes into action. The trigger could be its active ingredient, the adhesive, or some other component of the patch.
Once your body is sensitized to a compound, future reactions take place pretty quickly. The redness and irritation often spread past the point where a patch has had contact with the skin and the itching can be severe, taking days to calm down after removing the patch.
Nickel allergy is an example of allergic dermatitis. I cannot wear stainless steel or white gold necklaces or earrings for more than a few hours because they cause my entire earlobe to swell, get red and itch, itch, itch!
How can you help someone who is itching from wearing a patch?
1. First, try to determine whether it is an allergic reaction or not. If in doubt, call the doctor or make an appointment.
2. Treat your skin gently. Minimize irritation by using lukewarm instead of hot water when bathing or taking a shower, and don’t use rubbing alcohol or other solvents on your skin.
3. Don’t apply moisturizer to the area right before putting on a new patch, as that can cause the adhesive to fail.
4. Avoid washing the skin right before applying a new patch, as that can trap soap residue or moisture underneath the patch, causing irritation.
5. Remove the patch gently and apply a corticosteroid cream to the area, either 1% hydrocortisone or a prescription-strength cream from your doctor. If you have excess adhesive on your skin left from the patch, don’t scrub it off. Instead, wipe it off with Petroleum jelly or Bag Balm®.
6. Here’s a trick that may help reduce irritation: apply a liquid antacid like Maalox® or Mylanta® lightly to the skin with a cotton ball and let it dry before applying the patch.