Medically reviewed by Drugs.com. Last updated on Jun 11, 2021.
Commonly used brand name(s)
In the U.S.
- Fostex Cream
- Night Cast R
Available Dosage Forms:
Therapeutic Class: Antiacne Keratolytic
Pharmacologic Class: NSAID
Chemical Class: Salicylate, Non-Aspirin
Uses for SAStid
Salicylic acid and sulfur combination is used to treat acne and other skin disorders and dandruff and other scalp disorders, such as seborrheic dermatitis.
This medicine is available without a prescription.
Before using SAStid
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Young children may be at increased risk of unwanted effects because of increased absorption of salicylic acid through the skin. Products containing salicylic acid should not be applied to large areas of the body or used for long periods of time in infants and children.
Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of salicylic acid and sulfur combination in the elderly with use in other age groups.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Amtolmetin Guacil
- Bismuth Subsalicylate
- Choline Magnesium Trisalicylate
- Choline Salicylate
- Ethacrynic Acid
- Flufenamic Acid
- Magnesium Salicylate
- Mefenamic Acid
- Niflumic Acid
- Nimesulide Beta Cyclodextrin
- Pentosan Polysulfate Sodium
- Phenyl Salicylate
- Salicylic Acid
- Sodium Salicylate
- Tenofovir Disoproxil Fumarate
- Tiaprofenic Acid
- Tolfenamic Acid
- Trolamine Salicylate
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Azilsartan Medoxomil
- Candesartan Cilexetil
- Olmesartan Medoxomil
- Perindopril Erbumine
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Proper use of SAStid
This section provides information on the proper use of a number of products that contain salicylic acid and sulfur. It may not be specific to SAStid. Please read with care.
Use this medicine only as directed. Do not use more of it and do not use it more often than recommended on the label, unless otherwise directed by your doctor.
Immediately after using this medicine, wash your hands to remove any medicine that may be on them.
Keep this medicine away from the eyes. If you should accidentally get some in your eyes, flush them thoroughly with water.
To use the skin cleansing lotion:
- After wetting the skin, apply this medicine with your fingertips or a wet sponge and rub in gently to work up a lather. Then rinse thoroughly and pat dry.
To use the shampoo or bar as a shampoo:
- Wet the hair and scalp with lukewarm water. Then apply enough medicine to work up a lather and rub into the scalp. Continue rubbing the lather into the scalp for several minutes or allow it to remain on the scalp for about 5 minutes, depending on the product being used, then rinse. Apply the medicine again and rinse thoroughly.
To use the bar as a soap:
- After wetting the skin, use this medicine to wash the face and other affected areas. Then rinse thoroughly and pat dry.
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For acne or oily skin:
- For bar dosage form:
- Adults and children—Use on the affected skin two or three times a day.
- For cleansing lotion dosage form:
- Adults and children—Use on wet skin one to three times a day. Rub lather into skin for one minute then rinse.
- For bar dosage form:
- For dandruff and seborrheic dermatitis of the scalp:
- For bar and shampoo dosage forms:
- Adults and children—Use on the scalp once a day at least two times a week or as directed by doctor. May be used each day if needed.
- For bar and shampoo dosage forms:
If you miss a dose of this medicine, apply it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Precautions while using SAStid
When using salicylic acid and sulfur combination medicine, do not use any of the following preparations on the same affected area as this medicine, unless otherwise directed by your doctor:
- Abrasive soaps or cleansers
- Alcohol-containing preparations
- Any other topical acne preparation or preparation containing a peeling agent (for example, benzoyl peroxide, resorcinol, or tretinoin [vitamin A acid])
- Cosmetics or soaps that dry the skin
- Medicated cosmetics
- Other topical medicine for the skin
To use any of the above preparations on the same affected area as salicylic acid and sulfur combination medicine may cause severe irritation of the skin.
Do not use any topical mercury-containing preparation, such as ammoniated mercury ointment, on the same affected area as this medicine . To do so may cause a foul odor, may be irritating to the skin, and may stain the skin black. If you have any questions about this, check with your health care professional.
Taking large doses of aspirin or other salicylates (including diflunisal) while using topical salicylic acid (contained in this medicine) may lead to overdose. If you have any questions about this, check with your health care professional.
SAStid side effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- Skin irritation not present before use of this medicine
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
- Redness and peeling of skin (may occur after a few days)
- unusual dryness of skin
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
More about SAStid (salicylic acid / sulfur topical)
- Side Effects
- During Pregnancy
- Dosage Information
- Drug Interactions
- Drug class: miscellaneous topical agents
Related treatment guides
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.