The recommended dilution is 200 Units/2 mL, 200 Units/4 mL, 100 Units/1 mL, or 100 Units/2 mL with preservative-free 0.9% Sodium Chloride Injection, USP, depending on volume and number of injection sites desired to achieve treatment objectives (see Table 1). In general, no more than 50 Units per site should be administered using a sterile needle (e.g., 25-30 gauge) of an appropriate length. Localization of the involved muscles with electromyographic guidance may be useful.
As you noted in your question, the effects of Botox don't last forever. For some patients the short term effects of Botox are a ‘good thing,’ as it means that trying Botox is a relatively low risk/low commitment procedure. If you don't like your Botox results, there's not much to worry about: They will fade on their own in a few months. Generally speaking, the results last between three to five months -- but the duration of the Botox effect depends on the individual and on how many Botox units were used.

I increase the dose at each treatment cycle to 195 units. This is based on experience with patients with cervical dystonia, in whom higher doses result in a longer duration of effect. In addition, I transition to the next onabotulinumtoxinA treatment at 12 weeks by using occipital and trigeminal nerve blocks at 10 weeks. Most insurance companies will not cover onabotulinumtoxinA treatments earlier than 12 weeks, but in rare cases, 10-week cycles have been approved.

On July 7, 2015, the company acquired the rights to the late stage CGRP migraine portfolio of Merck & Co, as well as two experimental drugs (MK-1602 and MK-8031) for an upfront payment of $250 million.[12] On August 10, the company acquired Oculeve for $125 million.[13] On August 31, the company acquired Naurex for an upfront payment of $560 million.[14] On October 19, the company acquired AqueSys, developer of ocular implants that reduce intraocular pressure associated with glaucoma, for an initial payment of $300 million.[15] On October 1, the company acquired Kythera Biopharmaceuticals, a company focused on the medical aesthetics market, for $2.1 billion.[16] On November 4 the company announced the acquisition of Northwood Medical Innovation, developer of earFold, a medical device to correct protruding ears.[17] On November 25, 2015, the company announced it would partner with Rugen Therapeutic to develop new therapies for autism spectrum disorder, rabies and obsessive compulsive disorder.[18]

The results usually start to be noticed within three to 10 days or even sooner. They tend to last in most people for up to three or four months. As time passes, the muscle activity will gradually return to normal. Additionally, other areas may return to activity over time, depending on the amount injected. The interesting thing about Botox is that it tends to work fairly well even up to the third month, as a procedure that might last a very short time at full strength and then go away quickly (filler injections such as Restylane, Perlane, or Juvederm tend to last approximately six to 12 months, depending on the amount used).
So let's talk about it, shall we? And before we do, let's also get one thing out of the way—I've had Botox. And it was free. As a result, I've found myself trying to field questions about the price and popularity of certain treatments, and many times my knowledge on the subject comes up short. To remedy that fact, I decided to do some research into the real, unexaggerated pricing for injections and what each formula and technique will actually do to your face. Below find the answers you may have been looking for but didn't feel comfortable asking.

Who is injecting your Botox? Injecting Botox is deceptively easy. After all, it looks like the nurse or physician just takes a little fluid and squirts into facial muscles, and Walla ! Perfection! The answer is No! You should choose a specialist with years of experience and the ability to assess your facial features to create the best treatment plan possible. Because when Botox is injected in the wrong place it can produce unwanted side-effects that you might find disturbing. For instance if the injector “chases” a wrinkle across your forehead and it happens to be too close to your central eyebrow then the Botox or Dysport can drift downward inhibiting a muscle that lifts your eyelid resulting in a drooped upper eyelid. I know you don’t want that! Or if the practitioner injects only your “11” frown lines between your brows and does not inject other areas of your brow to balance out the effect then you may get a “boomerang”brow – a “Spock”-like overarched  brow that looks hideous. So like everything else experience counts but more experience usually translates into a more expensive treatment sessions. However, avoiding complications can save you money and aggravation in the long run.

Unopened vials of BOTOX should be stored in a refrigerator (2° to 8°C) for up to 36 months. Do not use after the expiration d ate on the vial. Administer BOTOX within 24 hours of reconstitution; during this period reconstituted BOTOX should be stored in a refrigerator (2° to 8°C). Reconstituted BOTOX should be clear, colorless, and free of particulate matter.
Absolutely. Botox (and competitors like Dysport and Xeomin, which will be widely available next January) are highly purified toxins that can temporarily erase or reduce horizontal forehead lines, vertical frown lines, and crow's-feet. "The injections slow muscles that contract hundreds of times a day, eventually etching lines in the skin," says New York City plastic surgeon Michael Kane, author of The Botox Book (St. Martin's Press). Botox can also lift the corners of the mouth that sag with age, smooth out the "pin cushion" look in some chins, soften smoker's lines around the mouth, and soften vertical neck cords.
There are no studies or adequate data from postmarketing surveillance on the developmental risk associated with use of BOTOX in pregnant women. In animal studies, administration of BOTOX during pregnancy resulted in adverse effects on fetal growth (decreased fetal weight and skeletal ossification) at clinically relevant doses, which were associated with maternal toxicity [see Data)].
As with all therapeutic proteins, there is a potential for immunogenicity. The detection of antibody formation is highly dependent on the sensitivity and specificity of the assay. Additionally, the observed incidence of antibody (including neutralizing antibo dy) positivity in an assay may be influenced by several factors including assay methodology, sample handling, timing of sample collection, concomitant medications, and underlying disease. For these reasons, comparison of the incidence of antibodies to onabotulinumtoxinA in the studies described below with the incidence of antibodies in other studies or to other products may be misleading.

Intradetrusor injection of BOTOX is contraindicated in patients with overactive bladder or detrusor overactivity associated with a neurologic condition who have a urinary tract infection. Intradetrusor injection of BOTOX is also contraindicated in patients with urinary retention and in patients with post-void residual (PVR) urine volume >200 mL, who are not routinely performing clean intermittent self-catheterization (CIC).
Botox can be bought by essentially any person with a DEA certificate. Allergan sells it in 50 and 100 unit vials. They are shipped overnight delivery on dry ice to keep the toxin effective it should be opened, reconstituted and used the same day ideally. The Botox will work best this way. Price points will change by who the injector is and what their motives are. Botox can be reconstituted so that you getting a very dilute amount of product. So a by the area approach may really only give you a small amount of product. Or you could be getting old Botox that is a week old and will not last for very long.

After an exam by a therapist and doctor, botulinum toxin for focal relief of muscle spasticity can be advised as the best way to address a child's functional problems. The problem muscle groups are identified, and goals for that child are discussed. Then the injection of botulinum toxin can be done if there are no permanent contractures of the muscle groups.
In Seattle, the cost usually ranges between 10$ and 16$ per unit. It varies depending on a few things. 1. Expertise of the injector, 2. Who the injector is (physician vs other), 3. Whether an office may be running a special. The number of units placed in an area can vary. For instance, for the frown lines between the eyebrows, studies show that the right amount for most women is 25 units. However, in my practice, I may put in as few as 10 (young female with a very petite forehead) or as many as 30 (larger forehead, strong frown line). We usually have 2-3 "botox" special events per year, and we also have an ongoing special price for VIP patients to reward them for coming to our clinic.
Focal Spasticity is a condition in which certain muscles in your body become stiff or tight. It is caused by damage to parts of the central nervous system that control voluntary movements. When this happens, your nerves send continuous messages to your muscles telling them to contract, or tighten. If you or someone you care for has stiffness in the muscles of the elbow, wrist, fingers, thumb, ankle, or toes, it could be Focal Spasticity.1