Doctor, doctor : Dr Tom Smith answers your questions

Will cod liver oil harm my unborn baby?

I am nine weeks pregnant. During the first seven weeks I took high-strength cod liver oil tablets, containing 800 units of vitamin A (retinol). Now I realise I may have damaged my baby. I read that excess of vitamin A can cause spina bifida, water on the brain, heart defects and a cleft palate.

Please put your mind at rest. The dose of vitamin A you took was very small compared with the doses that were originally linked with birth defects - and even then the risk was very low. The average vitamin A preparation contains 4,000 or 4,600 units per dose and the drops for children under four contain 5,000 units per dose. Now consider that you have absorbed and used up most of the vitamin A you swallowed, and that your baby received only a fraction of it, and you will see that he or she has not been exposed to an excessive amount. The risk must be very small indeed. Look forward to having a normal pregnancy and a beautiful baby.

My eyelid flickers every day

I have had a flickering left eyelid every day for two months and have been told it is due to being tired and run-down. Sometimes it flickers so fast, it makes me want to shut my eyes. Will it go away, or get worse?

You have described classical dystonia which derives from a disturbance in the nerve supplying the eyelid. You would have it regardless of being tired or run-down. Your form of dystonia is the mildest type - happily, it is unusual for this to spread into the other forms. Because your condition is spoiling the quality of your life, you would qualify for Botox treatment under the NHS. An expert injection into the correct spot will cure the flicker. Talk to your doctor - it was what Botox was designed for. Also, look up the Dystonia Society (dystonia.org.uk).

Dark hairs are worrying me

I am 21, female, and suffer from embarrassing dark hairs about an inch long on my neck and cheeks. I've tried bleaching and plucking, but neither works.

Please see your doctor, who will advise you. You may be asked to have hormone tests and even to see a skin specialist, as the hair may indicate a hormone imbalance. Two conditions come to mind: a low thyroid function and polycystic ovarian syndrome. Don't be shocked by this, but you need to rule them out. They can be treated, but only after the diagnosis is confirmed.

My wife's drugs fear

My wife has fibromyalgia: she has a lot of pain, is tired most of the time, and hardly ever gets a good night's sleep. Her doctor has suggested she take an antidepressant but she isn't keen on taking "chemicals". What is the evidence that they work?

The best comes from a review of 18 well-controlled trials in more than 1,400 people, mostly women. There was some evidence the older type of antidepressants ("tricyclics") helped reduce pain, improved sleep patterns and raised the quality of everyday living, but the differences were small. They did not help with fatigue. I'm worried that your wife is against "chemicals". Every medical treatment, as a prescription drug, herbal or "natural" therapy, is "chemical", and to work it has to have an effect on the body's biochemistry. She should talk to her doctor about her views on prescription medicines. If she has a negative attitude to them, they are unlikely to help her.

• Do you have a question for Dr Smith? Email doctordoctor@guardian.co.uk

Thanks to guardian.co.uk who have provided this article. View the original here.