I was diagnosed with polymyalgia rheumatica [swollen muscles] last April and was prescribed prednisolone. Since June, I have been on 2.5mg a day and will be taking it for at least another month. I take a multivitamin/mineral supplement and silica - nothing else for fear of interaction with the medication. Is there anything I could take to boost my immune system? I have had the flu jab for the past five years, but in the past two years I caught flu anyway. Should I stop taking it? I am a 62-year-old woman.

It is good that you are aware of the potential for interactions with conventional medicines as one of the major problems with taking supplements. Before taking any supplements it is best to wait until you have stopped the course of prednisolone. In fact, you should tell your GP that you are taking a multivitamin/mineral supplement and silica; they will then advise you accordingly. It would be unwise to discontinue your flu jab if you are susceptible to flu. One of the best ways to boost your immune system is any form of regular exercise of moderate intensity. In your case, a regular walk or even just exposure to the elements would have a beneficial effect. Also, don't forget nutrition is important, particularly vitamin C as a supplement or, even better, in fruit and vegetables.

I am a 28-year-old university student and suffer from hay fever. Unless I use my nasal inhaler, I sneeze constantly and am continuously blowing my nose. This has a real impact on my day and also affects my sleep. Are there any herbal products that would stop my symptoms?

Hay fever is a hypersensitivity reaction to seasonal allergens, leading to the characteristic symptoms of sneezing, itching, nasal blockage and red eyes. The best treatment is, of course, to avoid allergens altogether, but this is not usually practical. There is some evidence that butterbur (Petasites hybridus) is effective. It is, however, important for you to inform your GP if you are taking such remedies. Also, avoid using nasal inhalers and herbal remedies at the same time.

&#183: Max H Pittler is deputy director of complementary medicine, Peninsula Medical School, Universities of Exeter and Plymouth, and author of The Desktop Guide To Complementary And Alternative Medicine (Mosby). Before following Max's recommendations, you should consult your GP about any medical problems or special health conditions. Send your questions to Wellbeing, Guardian Weekend, 119 Farringdon Road, London EC1R 3ER. Email: ask.max@theguardian.com.