Could flip-flops be causing this horrible feeling in my foot?

QAI’ve got a painful area on the ball of my foot below my middle toes. It’s been uncomfortable for several months, but became much worse after I started wearing flip-flops in the last couple of weeks. There’s nothing to see on the skin and I can’t feel any lumps, so what should I do? This could be a Morton’s neuroma, a condition that affects the nerves that run between the metatarsals (the long bones in the foot), most commonly the nerve between the third and fourth. The nerve becomes thickened, leading to pain in the middle of the ball of the foot which can radiate into the toes, sometimes with burning, tingling or shooting pains.

Some describe the pain as if they are walking on a marble. The pain may be persistent or come and go, but it tends to be worse if you wear shoes that increase pressure on the ball of the foot such as high heels or flip-flops.

The condition can often be diagnosed by the symptoms and examining the foot, but if needed can be confirmed with an ultrasound scan. Sometimes just changing your footwear is all you need to relieve the discomfort, which means wearing shoes with plenty of padding and, if possible, adding in a shoe insert to sit under the ball of your foot.

A steroid and local anaesthetic injection can also be helpful. If this doesn’t work, then, surgery can be done, either making space around the nerve (decompression) or removing the thickened area of the nerve, though this can lead to numbness of the skin between the affected toes.

Morton’s neuroma is best dealt with by a chiropodist, so ask your GP about a referral.

Q

I’ve got a lump on my back which has been slowly getting bigger, so I couldn’t lie down in bed without being aware of it. My GP said it was a sebaceous cyst and advised the best way of dealing with it was to have it surgically removed, but that he could make it smaller by squeezing out the contents, so I opted for that. I couldn’t see what was happening, but the smell was awful. I was so embarrassed. Is there anything I can do to stop it coming back?

A

Sebaceous cysts, also known as epidermoid cysts, form from an overgrowth of the cells from the top layer of the skin. In most cases they are very small, like a pea, but can slowly enlarge so they are several centimetres across. They can develop anywhere on the body, but occur most commonly on the face, chest and upper back.

Why they form is a mystery and it’s nothing to do with cleanliness, but it seems that cells from the surface get into the deeper part of the skin, where they multiply, and the keratin they contain becomes soggy and forms into a cheese-like substance, which can smell like a very ripe blue cheese.

Your doctor will have expected this, so you really don’t have to worry.

Small cysts can be left alone but, if they grow large then the best treatment is surgical removal. Squeezing out the contents can bring relief if a cyst is uncomfortable and with current long waiting lists can be a sensible option. However, this can increase the chance of the cyst cavity becoming infected, so watch out for soreness. There is also a chance that the cavity will re-fill in the future.

Q

I’ve had depression for the last few months and have been having

a combination of therapy and sertraline antidepressants. I thought I’d feel better once the weather warmed up and the days got longer, but if anything the reverse has happened, so my doctor has suggested I switch to mirtazapine rather than increasing my current dose. Is this likely to help? What’s the difference between the two?

AThree different chemical messengers in the brain, known as neurotransmitters, affect mood: dopamine, noradrenaline and serotonin. The most commonly prescribed antidepressants, selective reuptake inhibitors (or SSRIs), can lift mood by increasing levels of serotonin activity in the brain. Several different types are available, including sertraline, citalopram and fluoxetine.

However, it can be trial and error finding one that works best for an individual, and one that is effective for you may not help another person, or may trigger bad side effects.

Generally, it’s advisable to take a drug for at least six weeks before switching and, depending on what dose you are taking, one option can be to increase this, though this does raise the risk of side effects such as altered sleep, drowsiness, nausea or sexual function problems.

It does sound, though, as if the sertraline you are currently taking is not being particularly effective, so switching to a different one may help.

One option could be to switch to a different type of SSRI, or alternatively a different type of antidepressant, which is what your GP has recommended.

Mirtazapine is one of a group of drugs known as SNRIs, which boost the activity of noradrenaline, as well as serotonin. This can be helpful for some people, though as with all antidepressants it can be difficult to predict what will work best.

SNRIs can be particularly helpful for those who have anxiety as well as depression, but side effects, such as a dry mouth and sleep disturbances, can be more of a problem.

Changing antidepressants, especially if you are on a fairly high dose, has to be done carefully and involves “cross tapering” – reducing the one you are stopping and gradually increasing the dose of the new one.

I suggest you talk again to your GP, who I’m sure will be able to explain the reason for her recommendation. ● If you have a health question for Dr Leonard, email her in confidence at yourhealth@express.co.uk. Dr Leonard regrets she cannot enter into personal correspondence or reply to everyone.