Irritant , counterirritants

Black mustard is a light olive-brown powder obtained by grinding the dried ripe seeds of several varieties of plants of the Brassica genus moisture yields from this, through enzymatic hydrolysis of a contained glycoside, are about 0.6% of the volatile oil of mustard, which has as its main ingredient the irritant compound allyl isothiocyanate. Mustard is available in bulk and as the official plaster, the latter used only for the local irritant (counterirritant) properties it develops when applied to the skin after moistening with tepid water. 

Theoretically, the risk of serious GI adverse events should be less than with oral NSAIDs, but long-term studies evaluating these events are lacking.38 Studies comparing topical NSAIDs with other topical products, including counterirritants, are also needed.35 Local cutaneous adverse reactions (e.g., erythema, pruritus, and irritation) occur in 1% to 2% of patients and may be due in part to the vehicle used.38... 

Counterirritants are categorized by the Food and Drug Administration (FDA) into four groups (groups A-D) based on their primary actions (Table 57-2). They produce a feeling of warmth, cooling, or irritation that diverts sensation from the primary source of pain. Because these irritant effects are central to the beneficial actions, counterirritants should not be combined with topical anesthetics or topical analgesics. 

Recommend appropriate pharmacologic therapy and educate on proper use. If a counterirritant is recommended, counsel patients on the irritant effect of the product and recommend washing hands immediately after use and to avoid heating pads. For patients using a capsaicin product, emphasize that adherence to regular application is required for effectiveness. 

Rubefacient An agent applied to the skin that causes local irritation and redness used to relieve pain by a counterirritant mechanism. 

Counterirritants and rubefacients are irritants that stimulate nerve endings in intact skin to relieve pain in skin (e.g. postherpetic), viscera or muscle supplied by the same nerve root. All produce inflammation of the skin which becomes flushed, hence rubefacients. They are often effective though their precise mode of action is imknown. 

Veratrla, veratrlne A mixture of alkaloids (chiefly cevadlne and veratrldlne) obtained as a white or grayish powder from sabadtUa seeds and used as a counterirritant in neuralgia and arthritis. It is an intense local irritant and a powerful muscle and nerve poison. 

Almost colorless to slightly yellow liquid with an aromatic, pungent odor and the taste of ammonia, d 0.90. Forms an opalescent mixture with water miscible with alcohol. therap CAT Reflex respiratory stimulant. therap cat (vei) By inhalation respiratory and circulatory stimulant. Internally expectorant, diaphoretic, antacid, carminative. Externally counterirritant, and in dilut -ed form to relieve the irritation of insect stings and bites. 

Counterirritant Substance applied to the skin that produces an irritation, heating, or vasodilating action. Generally, it speeds healing by increasing blood circulation and warming deep (usually joint) inflammations. 

The mechanism of menthol interaction in the body, as mentioned above, is confirmed by other studies. Willis et al. [42] concluded that menthol in mentholated cigarettes acts as a counterirritant that diminishes the chemosensory responses of inhaled irritants. Irritations were elicited in mice by irritants that occur in cigarette smoke (acrolein, acetic acid, cyclohexanone) and menthol abolished the irritation... 

Volatile mustard oil (or allyl isothiocyanate) is an extremely powerful irritant and produces blisters on the skin. It is also tear producing (lachrymatory) and has counterirritant properties when greatly diluted (e.g., 1 in 50). It should not be tasted or inhaled when undiluted. It is one of the most toxic essential oils (gosselin jiangsu martindale). ... 

Uses Coemulsifier, superfatting agent, emollient, counterirritant, wetting agent, solubilizer, dispersant for personal care prods., topical pharmaceuticals, soap and cleansing scrubs anti-irritant for anionic and amphoteric systems Properties Pale yei. cl. Iiq. sol. in ethanol, oleyl alcohol, IPA partly sol. in min. oil disp. in water, propylene glycol HLB 10.0 acid no. 2 max. sapon. no. 90-100 hyd.no. 155-170 Use Level 1-10%... 

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