General Skin Problems

Skin problems are often caused by localized infection, allergy, or irritation. They are not usually serious, although widespread skin problems may be distressing. You should consult your doctor if a skin problem lasts more than a month or causes severe discomfort; a new lump appears, especially if it is dark-coloured; or a sore fails to heal.

  • What type of skin problem do you have?

    • Rash

      Do you have a fever – a temperature of 38°C (100.4°F) or above?

      • Fever
      • No fever

        Is the affected skin itchy?

        • Itchy

          What does the affected skin look like?

          • Areas of inflamed skin with a scaly surface

            What do the edges of the rash look like?

            • Merge into surrounding skin
              • Possible cause Seborrhoeic dermatitis or eczema may be causing your rash.

                Self-help Avoid using harsh soaps or detergents on the skin. A mild emollient cream should help to soothe the rash. Make an appointment to see your doctor if your rash does not improve within 1 week or if other symptoms develop.

            • Clearly defined margins
              • Possible cause Ringworm may be the cause of your rash.

                Medical help Make an appointment to see your doctor.

          • One or more red bumps with a central dark spot
            • Possible cause Insect bites may be the cause of such itchy bumps.

              Self-help Soothe the irritation with cold compresses. Get medical help at once if you are allergic to bites or stings.

          • One or more red raised areas (weals) that come and go
            • Possible cause Urticaria is possible.

              Self-help Soothe the irritation with cold compresses or calamine lotion. Over-the-counter antihistamine tablets may help. Get medical advice at once if breathing difficulties develop.

          • None of the above

            Does either of the following apply?

            • You have a rash that spreads out from a central red spot
              • Possible cause There is a possibility that you have Lyme disease.

                Medical help See your doctor within 24 hours.

            • You have been bitten by a tick
              • Possible cause There is a possibility that you have Lyme disease.

                Medical help See your doctor within 24 hours.

            • Neither

              Are you currently taking any medications or complementary remedies?

              • Yes
                • Possible cause Your symptoms may be a side effect of the medication or remedy.

                  Medical help URGENT! Phone your doctor immediately! He or she may advise you to stop taking a particular medication.

              • No
                • If you cannot identify a possible cause for your skin problem from this chart, make an appointment to see your doctor.

        • Not itchy

          Does your skin problem fit any of the following descriptions?

          • A painful, blistery rash in only one area on one side of the body
            • Possible cause Shingles (see Herpes zoster) is a possible cause of this type of rash.

              Medical help See your doctor within 24 hours.

          • Reddened patches covered with silvery scales
            • Possible cause Psoriasis can produce this type of rash.

              Medical help Make an appointment to see your doctor.

          • Blistery, oozing rash on or around the lips
            • Possible cause You may have impetigo. However, if this is a recurring problem, a cold sore is more likely.

              Medical help See your doctor within 24 hours if the diagnosis is not clear. For cold sores, use self-help measures.

          • A painful red lump with a yellow centre
            • Possible cause This may be a boil.

              Self-help Follow the self-help measures for a boil. Phone your doctor if the condition has not improved in 24 hours.

          • None of the above

            Does either of the following apply?

            • You have a rash that spreads out from a central red spot
              • Possible cause There is a possibility that you have Lyme disease.

                Medical help See your doctor within 24 hours.

            • You have been bitten by a tick
              • Possible cause There is a possibility that you have Lyme disease.

                Medical help See your doctor within 24 hours.

            • Neither

              Are you currently taking any medications or complementary remedies?

              • Yes
                • Possible cause Your symptoms may be a side effect of the medication or remedy.

                  Medical help URGENT! Phone your doctor immediately! He or she may advise you to stop taking a particular medication.

              • No
                • If you cannot identify a possible cause for your skin problem from this chart, make an appointment to see your doctor.

    • Other skin problem

      Have you noticed any of the following?

      • Red, tender, and hot area of skin
        • Possible cause Cellulitis may be the cause of your symptoms.

          Medical help URGENT! Phone your doctor immediately!

      • New mole or a change in an existing mole
        • Possible cause Skin cancer is a possible cause.

          Medical help Make an appointment to see your doctor.

      • An open sore that has not healed after 3 weeks
        • Possible cause Skin cancer is a possible cause.

          Medical help Make an appointment to see your doctor.

      • Hard, skin-coloured lump on hand or sole
        • Possible causes This is likely to be a wart or verruca (see Warts), or a callus (see Calluses and corns).

          Medical help Make an appointment to see your doctor if you are uncertain about the diagnosis.

      • None of the above

        Is the affected skin itchy?

        • Itchy

          What does the affected skin look like?

          • Areas of inflamed skin with a scaly surface

            What do the edges of the rash look like?

            • Merge into surrounding skin
              • Possible cause Seborrhoeic dermatitis or eczema may be causing your rash.

                Self-help Avoid using harsh soaps or detergents on the skin. A mild emollient cream should help to soothe the rash. Make an appointment to see your doctor if your rash does not improve within 1 week or if other symptoms develop.

            • Clearly defined margins
              • Possible cause Ringworm may be the cause of your rash.

                Medical help Make an appointment to see your doctor.

          • One or more red bumps with a central dark spot
            • Possible cause Insect bites may be the cause of such itchy bumps.

              Self-help Soothe the irritation with cold compresses. Get medical help at once if you are allergic to bites or stings.

          • One or more red raised areas (weals) that come and go
            • Possible cause Urticaria is possible.

              Self-help Soothe the irritation with cold compresses or calamine lotion. Over-the-counter antihistamine tablets may help. Get medical advice at once if breathing difficulties develop.

          • None of the above

            Does either of the following apply?

            • You have a rash that spreads out from a central red spot
              • Possible cause There is a possibility that you have Lyme disease.

                Medical help See your doctor within 24 hours.

            • You have been bitten by a tick
              • Possible cause There is a possibility that you have Lyme disease.

                Medical help See your doctor within 24 hours.

            • Neither

              Are you currently taking any medications or complementary remedies?

              • Yes
                • Possible cause Your symptoms may be a side effect of the medication or remedy.

                  Medical help URGENT! Phone your doctor immediately! He or she may advise you to stop taking a particular medication.

              • No
                • If you cannot identify a possible cause for your skin problem from this chart, make an appointment to see your doctor.

        • Not itchy

          Does your skin problem fit any of the following descriptions?

          • A painful, blistery rash in only one area on one side of the body
            • Possible cause Shingles (see Herpes zoster) is a possible cause of this type of rash.

              Medical help See your doctor within 24 hours.

          • Reddened patches covered with silvery scales
            • Possible cause Psoriasis can produce this type of rash.

              Medical help Make an appointment to see your doctor.

          • Blistery, oozing rash on or around the lips
            • Possible cause You may have impetigo. However, if this is a recurring problem, a cold sore is more likely.

              Medical help See your doctor within 24 hours if the diagnosis is not clear. For cold sores, use self-help measures.

          • A painful red lump with a yellow centre
            • Possible cause This may be a boil.

              Self-help Follow the self-help measures for a boil. Phone your doctor if the condition has not improved in 24 hours.

          • None of the above

            Does either of the following apply?

            • You have a rash that spreads out from a central red spot
              • Possible cause There is a possibility that you have Lyme disease.

                Medical help See your doctor within 24 hours.

            • You have been bitten by a tick
              • Possible cause There is a possibility that you have Lyme disease.

                Medical help See your doctor within 24 hours.

            • Neither

              Are you currently taking any medications or complementary remedies?

              • Yes
                • Possible cause Your symptoms may be a side effect of the medication or remedy.

                  Medical help URGENT! Phone your doctor immediately! He or she may advise you to stop taking a particular medication.

              • No
                • If you cannot identify a possible cause for your skin problem from this chart, make an appointment to see your doctor.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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