THE DOC REPLIES

What causes a stye? I’m often troubled by them and wondered if there was an underlying reason.

A stye is usually caused by a bacterial infection in one of the glands of the eyelid, or at the base of an eyelash. These are usually self-limiting and resolve within one or two weeks. Styes can vary in their size and discomfort, depending on which structure is affected. Simple over-thecounter painkillers or a warm compress can help manage the symptoms.

Is there a case to legalise marijuana use for pain relief?

Marijuana remains an illegal drug due to the potential health implications and addictive properties. Certain compounds of this drug, called cannabinoids, may have use in the future for managing pain, and there are ongoing clinical trials. But the legalisation of marijuana in its pure form may not be the answer.

My hands go red, from the tips to the wrists, in the evening. Any ideas?

The skin of the hands can change colour for a number of different reasons and in a number of different conditions. This is primarily at night. It could be related to a very rare condition called erythromyalgia. In this condition patients usually notice burning associated with itch, initially, before it becomes more progressive. As well as changes in colour and pain there is usually tenderness and swelling. However, this condition often usually affects the feet as well as the hands. Raynaud’s phenomenon can also cause colour changes to hands including redness, and so can some nerve-related conditions.

I’m troubled by prickly heat in warm weather. How can I avoid it?

Try to avoid excessive heat and humidity. If you do need to go out in extreme heat, use a small fan or spend time in the shade. Wearing loose cotton clothing will help keep you cool as well as taking a cool bath or shower. If you are unfortunate enough to get prickly heat, calomine lotion and antihistamine tablets can help the itch. Avoiding becoming dehydrated can also help – drinking plenty of water is essential in hot weather.

I’m 78 and eat a relatively small amount – a bowl of porridge and half a tin of sardines a day. My BMI is 25.5. Is this normal?

This seems a rather small amount. Healthy eating requires a varied and balanced diet. Further advice regular amounts of diary, protein, carbohydrate and fats can be found on the NHS Choices and NHS Inform websites.

I’m woken in the morning by pain in what feels like my kidneys. Could it be kidney stones?

The pain of kidney stones is usually very intense and onesided, affecting only the left or the right kidney. It is generally located under the rib cage in the flank and can come in waves. Occasionally, depending on the location of the stone, this can travel down to the groin. If you are having recurrent pain, and this is persisting over a period of time, it may be worth seeing your GP.

I’m going camping soon. What’s the best way to protect against ticks? Ticks are found in wooded areas and in high grass. You can avoid them by walking in areas that are unlikely to have ticks, or making sure that there is limited exposed skin on the areas coming into contact with the environment. After walking in these areas it would be sensible to then check your skin. They can be removed with a tick remover.

What is cholestasis in pregnancy?

This is a problem with the flow of bile acid from your liver towards the gut. The main symptom is usually intense itch often more notable in the hands and feet. Itching can be common in pregnancy but you can discuss this with your midwife or GP if you’re concerned.