Rocky1, I am sorry about your dog, and absolutely liver is a KNOWN side effect, albeit small, with the drug. So anyone doubting you needs to do some research.
However, your other information is a not accurate.
first, no, clomicalm is not the doggy form of prozac.
Second, 5-htp has toxicity also. Almost no drug comes without risks. http://www.ncbi.nlm.nih.gov/pubmed/10863592
Add to the fact that prozac has been used and researched heavily, whereas research on 5-HTP is scarce in humans and almost nonexistent in dogs beyond the toxicity above. "natural" doesn't mean safe.
In humans it also can cause liver damage
Tryptophan use has been associated with the development of serious conditions, such as liver and brain toxicity, and with eosinophilic myalgia syndrome (EMS), a potentially fatal disorder that affects the skin, blood, muscles, and organs (see "Overview" section). Such reports prompted the FDA to ban the sale of all tryptophan supplements in 1989. As with tryptophan, EMS has been reported in 10 people taking 5-HTP.
Side effects of 5-HTP are generally mild and may include nausea, heartburn, gas, feelings of fullness, and rumbling sensations in some people. At high doses, serotonin syndrome, a dangerous condition caused by too much serotonin in the body, could develop. Talk to your health care provider before taking higher-than-recommended doses.
People with high blood pressure or diabetes should talk to their doctor before taking 5-HTP.
If you take antidepressants, you should not take 5-HTP (see "Possible Interactions" section).
People with liver disease, pregnant women, and women who are breastfeeding should not take 5-HTP.<<
Clomicalm (clomipramine hydrochloride) is a tricyclic antidepressant and affects chemicals in the brain (serotonin)
Prozac, fluoxetine, is a selective serotonin reuptake inhibitor (SSRI) antidepressant drug . Its FDA-approved veterinary formulation is known as Reconcile.
Clomicalm slows the reabsorption rate of the neurotransmitters serotonin and norepinephrine, allowing their levels to rise in the brain. This drug is mainly used to treat separation anxiety. Prozac, on the other hand, works by strongly blocking the reabsorption of serotonin allowing more serotonin to be available for extended periods of time.
Prozac, clomicalm and 5-HTP can all cause liver issues.