Question: What is the active ingredient in the product Freederm that treats acne?

Context paragraphs:
Delsym: Delsym is a brand of cough medicine owned by Reckitt Benckiser, and manufactured at Unither Manufacturing in Rochester, NY.  It is different from most brands of cough medicine in that the active ingredient is "time released".  The time release feature allows the drug to suppress the cough reflex for a longer period of time.  The active ingredient per teaspoon (5 mL) is dextromethorphan polistirex, equivalent to dextromethorphan HBr 30 mg.

Active ingredient: An active ingredient (AI) is the ingredient in a pharmaceutical drug that is biologically active.  The similar terms active pharmaceutical ingredient (API) and bulk active are also used in medicine, and the term active substance may be used for natural products.  Some medication products may contain more than one active ingredient.  The traditional word for the API is pharmacon or pharmakon (from Greek: φάρμακον , adapted from pharmacos) which originally denoted a magical substance or drug.

International nonproprietary name: An international nonproprietary name (INN) is an official generic and nonproprietary name given to a pharmaceutical drug or active ingredient.  International nonproprietary names make communication more precise by providing a unique standard name for each active ingredient, to avoid prescribing errors.  The INN system has been coordinated by the World Health Organization (WHO) since 1953.

Nitroglycerin: Nitroglycerin (NG), also known as nitroglycerine, trinitroglycerin (TNG), trinitroglycerine, nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a heavy, colorless, oily, explosive liquid most commonly produced by nitrating glycerol with white fuming nitric acid under conditions appropriate to the formation of the nitric acid ester.  Chemically, the substance is an organic nitrate compound rather than a nitro compound, yet the traditional name is often retained.  Invented in 1847, nitroglycerin has been used as an active ingredient in the manufacture of explosives, mostly dynamite, and as such it is employed in the construction, demolition, and mining industries.  Since the 1880s, it has been used by the military as an active ingredient, and a gelatinizer for nitrocellulose, in some solid propellants, such as cordite and ballistite.

Freederm: Freederm is a UK brand of acne and skin care medication manufactured by Diomed Developments Limited.  The products include Nicotinamide as an active ingredient, which is claimed by the company to be "clinically proven to help get rid of inflamed red spots".

Ambroxol: Ambroxol is a secretolytic agent used in the treatment of respiratory diseases associated with viscid or excessive mucus.  Recently, a hypothesis suggested that it may have a potential role in treatment of Paget's disease of bone, Parkinsonism and other common autophagy-mediated aging diseases It is the active ingredient of Mucosolvan, Mucobrox, Mucol, Lasolvan, Mucoangin, Surbronc, Ambolar, and Lysopain.  The substance is a mucoactive drug with several properties including secretolytic and secretomotoric actions that restore the physiological clearance mechanisms of the respiratory tract, which play an important role in the body’s natural defence mechanisms.  It stimulates synthesis and release of surfactant by type II pneumocytes.  Surfactant acts as an anti-glue factor by reducing the adhesion of mucus to the bronchial wall, in improving its transport and in providing protection against infection and irritating agents.  Ambroxol is often administered as an active ingredient in cough syrup.

Excipient: An excipient is a substance formulated alongside the active ingredient of a medication, included for the purpose of long-term stabilization, bulking up solid formulations that contain potent active ingredients in small amounts (thus often referred to as "bulking agents", "fillers", or "diluents"), or to confer a therapeutic enhancement on the active ingredient in the final dosage form, such as facilitating drug absorption, reducing viscosity, or enhancing solubility.  Excipients can also be useful in the manufacturing process, to aid in the handling of the active substance concerned such as by facilitating powder flowability or non-stick properties, in addition to aiding "in vitro" stability such as prevention of denaturation or aggregation over the expected shelf life.  The selection of appropriate excipients also depends upon the route of administration and the dosage form, as well as the active ingredient and other factors.

Nicotinamide: Nicotinamide (NAA), also known as niacinamide, is a vitamin found in food, used as a dietary supplement, and used as a medication.  As a supplement, it is used by mouth to prevent and treat pellagra (niacin deficiency).  While nicotinic acid (niacin) may be used for this purpose, nicotinamide has the benefit of not causing skin flushing.  As a cream, it is used to treat acne.

Stridex: Stridex (originally spelled Stri-Dex) is an American acne treatment and prevention medicine, originally registered trademark of Bayer Corporation.  It comes in the form of fibrous pads saturated with astringents and contained in a plastic tub of fifty-five to ninety pads.  Most products in the Stridex line contain as the active ingredient salicylic acid (0.5–2.5%); Stridex "Power Pads", however, contain instead benzoyl peroxide (2.5%), which is considered by medical professionals to be "the most effective and widely used nonprescription medication for both types of acne".  However, they also warn about possible side effects: dryness of the skin, possible burning, and tingling.  Patients are advised to apply treatment with caution around lips, nose and mouth, or cuts and scrapes, and also avoid excessive sun exposure.  In 2013, FDA started to investigate a possible link between benzoyl peroxide- and/or salicylic acid-based acne prevention medicine with hypersensitivity and anaphylactic reactions without calling off any products or placing warnings.

Driclor: Driclor is a strong anti-perspirant manufactured by Stiefel Laboratories (UK) and produced in Sligo, Ireland.  Driclor is similar to other strong anti-perspirants using 20% aluminium chloride hexahydrate as the active ingredient, however, the water content and roll-on dispenser may cause skin irritancy as water / perspiration can break down the active ingredient to produce hydrochloric acid.

Supporting paragraphs: Freederm Nicotinamide
Answer: Nicotinamide