Since some of you may have some general questions lingering about permanent waving, I'll quickly go over some generalities that might some common issues:
1. Ammonium thioglycolate, the active ingredient in permanent waves, is extremely drying to the hair. Proper moisturizing is therefore a must, accomplished by applying glycerin and propylene glycol-rich sprays, cremes, lotions and/or gels on a frequent basis. A good hydrating and detangling shampoo should be used for cleansing, followed by a deep penetrating re-moisturizing treatment.
2. With repeat perm applications (every 12 weeks or so to treat new growth), the previously permed hair loses additional cystine bonds and incurs greater damage. As a result, the hair is further dehydrated, and the ends may become straight, stringy or broken. A great deal of care, therefore, must be taken to condition the hair well after every shampoo, and the ends should be trimmed with each repeat application.
3. Due to market demand, manufacturers typically package professional perm processing components in bulk sizes. Thioglycolate in Rearrangers or Reshaping Creams and lotions loses efficacy over time and exposure to air. Due to this fact, professional permanent wave products are subject to inconsistent performance, yielding unpredictable results. Therefore, it is recommended that stylists purchase more moderate-sized components for perming and refrain from leaving the jars and bottles open longer than absolutely necessary.
4. As sleeker styles come into vogue, many clients have requested transitions to relaxed hair. Permed hair definitely should not be treated with standard relaxer formulas since sodium hydroxide, as well as guanidine hydroxide (no-lye formulas), react very rapidly on permed hair, inducing excessive damage. Clients must be counseled to wait until there is sufficient new growth before a relaxer treatment is applied, and advised that eventually the permed portion of the hair will have to be cut off. "Restructuring" from curly to straight may be attempted with mild guanidine hydroxide relaxers when there is sufficient new growth. In this process, the relaxer is combed through the previously permed hair only during the final 2-3 minutes of processing.
5. Despite the marketing promises of many brands, permanent waves cannot effectively go through significant style transformations (i.e., from the original curly texture, to a straight relaxed look, and back to curly again) on a repetitive basis. The client will not like the end result. Manipulation of permed hair with heated appliances such as blow dryers and curling irons, and even roller sets, will weaken the curl pattern significantly. After repeated attempts to achieve a relaxed look, the perm will not spring back to its original form.