A swab is a small stick with a patch of foam, cotton, or similar material mounted on one end. Swabs are useful for a variety of medical procedures like taking samples for culture or applying medication to mucous membranes. Numerous manufacturers produce a range of designs for medical use, and doctors can custom order swabs for particular purposes. Some products are readily available at drug stores; many homes, for example, have a small box of loose cotton swabs for cleaning out the ears.
Some swabs come in a loose package and are not sterile, although they are clean. It is also possible to buy individually packaged products sealed in plastic. These are useful for taking samples, as the physician does not want to use a contaminated tool for this purpose. The doctor can open the package and swipe the swab along an area of interest, like the inner cheek for a DNA sample or the surface of a skin infection for a microbial culture. The sample goes back into a sealed container for analysis in a laboratory.
Medicated swabs are also available. Patients can use a clean cotton swab for a task like applying a medicated cream, or they can buy a specially made swab. It usually has a breakable rod inside that the patient snaps to release a dose of the medication into the tip. It can be applied topically to treat infection, inflammation, or other issues. Some drugstores carry topical swabs for cold sores and minor cuts and scrapes, and others are available by prescription only.
Another use for a swab can be the gentle manipulation of tissue so a doctor can examine it. The hands may be large enough to obscure what the doctor is trying to see, and she can use the tool to gently push or lift the tissue without handling it directly. In cases where the doctor needs both hands free, an assistant can handle the swab as directed. Larger absorbent swabs are available for cleaning out fluids during medical procedures like lancing an abscess.
The material used in swab construction is usually hypoallergenic, and patients should not experience contact dermatitis when a doctor uses a swab. With medicated swabs, there can be a risk of reacting to the medication. Patients with a history of allergies should discuss this with a doctor or pharmacist before accepting a prescription. The doctor can determine if the medication is safe and prescribe an alternative if it appears to be necessary.